diff --git a/src/app/Backends/Storage.php b/src/app/Backends/Storage.php
--- a/src/app/Backends/Storage.php
+++ b/src/app/Backends/Storage.php
@@ -126,7 +126,8 @@
         // Update the file type and size information
         $file->setProperties([
                 'size' => $fileSize,
-                'mimetype' => self::mimetype($path),
+                // Pick the client-supplied mimetype if available, otherwise detect.
+                'mimetype' => !empty($params['mimetype']) ? $params['mimetype'] : self::mimetype($path),
         ]);
 
         // Assign the node to the file, "unlink" any old nodes of this file
diff --git a/src/app/Fs/Item.php b/src/app/Fs/Item.php
--- a/src/app/Fs/Item.php
+++ b/src/app/Fs/Item.php
@@ -24,7 +24,7 @@
     use UuidStrKeyTrait;
 
     public const TYPE_FILE       = 1;
-    public const TYPE_FOLDER     = 2;
+    public const TYPE_COLLECTION = 2;
     public const TYPE_INCOMPLETE = 4;
 
     /** @var array<int, string> The attributes that are mass assignable */
@@ -167,4 +167,34 @@
             );
         }
     }
+
+    /**
+     * Relations for this user
+     *
+     * @return \Illuminate\Database\Eloquent\Relations\HasMany
+     */
+    public function relations()
+    {
+        return $this->hasMany(Relation::class);
+    }
+
+    /**
+     * Relations for this item
+     *
+     * @return \Illuminate\Database\Eloquent\Relations\BelongsToMany
+     */
+    public function children()
+    {
+        return $this->belongsToMany(Item::class, 'fs_relations', 'item', 'related');
+    }
+
+    /**
+     * Relations for this item
+     *
+     * @return \Illuminate\Database\Eloquent\Relations\BelongsToMany
+     */
+    public function parents()
+    {
+        return $this->belongsToMany(Item::class, 'fs_relations', 'related', 'item');
+    }
 }
diff --git a/src/app/Fs/Relation.php b/src/app/Fs/Relation.php
new file mode 100644
--- /dev/null
+++ b/src/app/Fs/Relation.php
@@ -0,0 +1,21 @@
+<?php
+
+namespace App\Fs;
+
+use Illuminate\Database\Eloquent\Casts\Attribute;
+use Illuminate\Database\Eloquent\Model;
+
+/**
+ * The eloquent definition of a filesystem item.
+ *
+ * @property string $id        Item identifier
+ * @property string $related   Item identifier
+ */
+class Relation extends Model
+{
+    /** @var array<int, string> The attributes that are mass assignable */
+    protected $fillable = ['item', 'related'];
+
+    /** @var string Database table name */
+    protected $table = 'fs_relations';
+}
diff --git a/src/app/Http/Controllers/API/V4/CompanionAppsController.php b/src/app/Http/Controllers/API/V4/CompanionAppsController.php
--- a/src/app/Http/Controllers/API/V4/CompanionAppsController.php
+++ b/src/app/Http/Controllers/API/V4/CompanionAppsController.php
@@ -247,7 +247,7 @@
                 'personal_access_client' => 0,
                 'password_client' => 1,
                 'revoked' => false,
-                'allowed_scopes' => "mfa"
+                'allowed_scopes' => ["mfa", "files"]
             ]);
             $client->save();
 
diff --git a/src/app/Http/Controllers/API/V4/FilesController.php b/src/app/Http/Controllers/API/V4/FsController.php
rename from src/app/Http/Controllers/API/V4/FilesController.php
rename to src/app/Http/Controllers/API/V4/FsController.php
--- a/src/app/Http/Controllers/API/V4/FilesController.php
+++ b/src/app/Http/Controllers/API/V4/FsController.php
@@ -13,7 +13,7 @@
 use Illuminate\Support\Facades\Cache;
 use Illuminate\Support\Facades\Validator;
 
-class FilesController extends RelationController
+class FsController extends RelationController
 {
     protected const READ = 'r';
     protected const WRITE = 'w';
@@ -35,7 +35,7 @@
     public function destroy($id)
     {
         // Only the file owner can do that, for now
-        $file = $this->inputFile($id, null);
+        $file = $this->inputItem($id, null);
 
         if (is_int($file)) {
             return $this->errorResponse($file);
@@ -45,6 +45,13 @@
         // storage later with the fs:expunge command
         $file->delete();
 
+        if ($file->type & Item::TYPE_COLLECTION) {
+            return response()->json([
+                    'status' => 'success',
+                    'message' => \trans('app.collection-delete-success'),
+            ]);
+        }
+
         return response()->json([
                 'status' => 'success',
                 'message' => \trans('app.file-delete-success'),
@@ -85,7 +92,7 @@
     public function getPermissions($fileId)
     {
         // Only the file owner can do that, for now
-        $file = $this->inputFile($fileId, null);
+        $file = $this->inputItem($fileId, null);
 
         if (is_int($file)) {
             return $this->errorResponse($file);
@@ -113,7 +120,7 @@
     public function createPermission($fileId)
     {
         // Only the file owner can do that, for now
-        $file = $this->inputFile($fileId, null);
+        $file = $this->inputItem($fileId, null);
 
         if (is_int($file)) {
             return $this->errorResponse($file);
@@ -174,7 +181,7 @@
     public function deletePermission($fileId, $id)
     {
         // Only the file owner can do that, for now
-        $file = $this->inputFile($fileId, null);
+        $file = $this->inputItem($fileId, null);
 
         if (is_int($file)) {
             return $this->errorResponse($file);
@@ -206,7 +213,7 @@
     public function updatePermission(Request $request, $fileId, $id)
     {
         // Only the file owner can do that, for now
-        $file = $this->inputFile($fileId, null);
+        $file = $this->inputItem($fileId, null);
 
         if (is_int($file)) {
             return $this->errorResponse($file);
@@ -264,15 +271,35 @@
     {
         $search = trim(request()->input('search'));
         $page = intval(request()->input('page')) ?: 1;
+        $parent = request()->input('parent');
+        $type = request()->input('type');
         $pageSize = 100;
         $hasMore = false;
 
         $user = $this->guard()->user();
 
-        $result = $user->fsItems()->select('fs_items.*', 'fs_properties.value as name')
-            ->join('fs_properties', 'fs_items.id', '=', 'fs_properties.item_id')
-            ->whereNot('type', '&', Item::TYPE_INCOMPLETE)
-            ->where('key', 'name');
+        $result = $user->fsItems()->select('fs_items.*', 'fs_properties.value as name');
+
+        if ($parent) {
+            $result->join('fs_relations', 'fs_items.id', '=', 'fs_relations.related')
+                ->where('fs_relations.item', $parent);
+        } else {
+            $result->leftJoin('fs_relations', 'fs_items.id', '=', 'fs_relations.related')
+                ->whereNull('fs_relations.related');
+        }
+
+        // Add properties
+        $result->join('fs_properties', 'fs_items.id', '=', 'fs_properties.item_id')
+                ->whereNot('type', '&', Item::TYPE_INCOMPLETE)
+                ->where('key', 'name');
+
+        if ($type) {
+            if ($type == "collection") {
+                $result->where('type', '&', Item::TYPE_COLLECTION);
+            } else {
+                $result->where('type', '&', Item::TYPE_FILE);
+            }
+        }
 
         if (strlen($search)) {
             $result->whereLike('fs_properties.value', $search);
@@ -316,7 +343,7 @@
      */
     public function show($id)
     {
-        $file = $this->inputFile($id, self::READ);
+        $file = $this->inputItem($id, self::READ);
 
         if (is_int($file)) {
             return $this->errorResponse($file);
@@ -328,7 +355,7 @@
             // Generate a download URL (that does not require authentication)
             $downloadId = Utils::uuidStr();
             Cache::add('download:' . $downloadId, $file->id, 60);
-            $response['downloadUrl'] = Utils::serviceUrl('api/v4/files/downloads/' . $downloadId);
+            $response['downloadUrl'] = Utils::serviceUrl('api/v4/items/downloads/' . $downloadId);
         } elseif (request()->input('download')) {
             // Return the file content
             return Storage::fileDownload($file);
@@ -345,6 +372,63 @@
         return response()->json($response);
     }
 
+    private function deduplicateOrCreate(Request $request, $type)
+    {
+        $user = $this->guard()->user();
+        $item = null;
+        if ($request->has('deduplicate-property')) {
+            //query for item by deduplicate-value
+            $result = $user->fsItems()->select('fs_items.*');
+            $result->join('fs_properties', function ($join) use ($request) {
+                $join->on('fs_items.id', '=', 'fs_properties.item_id')
+                ->where('fs_properties.key', $request->input('deduplicate-property'));
+            })
+            ->where('type', '&', $type);
+
+            $result->whereLike('fs_properties.value', $request->input('deduplicate-value'));
+            $item = $result->first();
+        }
+
+        if (!$item) {
+            $item = $user->fsItems()->create(['type' => $type]);
+        }
+        return $item;
+    }
+
+    /**
+     * Create a new collection.
+     *
+     * @param \Illuminate\Http\Request $request The API request.
+     *
+     * @return \Illuminate\Http\JsonResponse The response
+     */
+    private function createCollection(Request $request)
+    {
+        $item = $this->deduplicateOrCreate($request, Item::TYPE_COLLECTION);
+        $item->setProperties([
+            'name' => $request->input('name'),
+            'deviceId' => $request->input('deviceId'),
+            'collectionType' => $request->input('collectionType'),
+        ]);
+
+        foreach ($request->all() as $key => $value) {
+            if (str_starts_with($key, "property-")) {
+                $item->setProperty(substr($key, 9), $value);
+            }
+        }
+
+        if ($parent = $request->input('parent')) {
+            $item->parents()->sync([$parent]);
+        }
+
+        $response = [];
+        $response['status'] = 'success';
+        $response['id'] = $item->id;
+        $response['message'] = \trans('app.collection-create-success');
+
+        return response()->json($response);
+    }
+
     /**
      * Create a new file.
      *
@@ -354,10 +438,13 @@
      */
     public function store(Request $request)
     {
-        $user = $this->guard()->user();
+        $type = $request->input('type');
+        if ($type == "collection") {
+            return $this->createCollection($request);
+        }
 
         // Validate file name input
-        $v = Validator::make($request->all(), ['name' => ['required', new FileName($user)]]);
+        $v = Validator::make($request->all(), ['name' => ['required', new FileName()]]);
 
         if ($v->fails()) {
             return response()->json(['status' => 'error', 'errors' => $v->errors()], 422);
@@ -366,12 +453,8 @@
         $filename = $request->input('name');
         $media = $request->input('media');
 
-        // FIXME: Normally people just drag and drop/upload files.
-        // The client side will not know whether the file with the same name
-        // already exists or not. So, in such a case should we throw
-        // an error or accept the request as an update?
-
         $params = [];
+        $params['mimetype'] = $request->headers->get('Content-Type', null);
 
         if ($media == 'resumable') {
             $params['uploadId'] = 'resumable';
@@ -380,10 +463,24 @@
         }
 
         // TODO: Delete the existing incomplete file with the same name?
-
-        $file = $user->fsItems()->create(['type' => Item::TYPE_INCOMPLETE | Item::TYPE_FILE]);
+        $file = $this->deduplicateOrCreate($request, Item::TYPE_FILE);
         $file->setProperty('name', $filename);
 
+        foreach ($request->all() as $key => $value) {
+            if (str_starts_with($key, "property-")) {
+                $file->setProperty(substr($key, 9), $value);
+            }
+        }
+
+        if ($parentHeader = $request->headers->get('X-Kolab-Parents', null)) {
+            $parents = explode(',', $parentHeader);
+            $file->parents()->sync($parents);
+        }
+
+        if ($parent = $request->input('parent')) {
+            $file->parents()->sync([$parent]);
+        }
+
         try {
             $response = Storage::fileInput($request->getContent(true), $params, $file);
 
@@ -412,12 +509,26 @@
      */
     public function update(Request $request, $id)
     {
-        $file = $this->inputFile($id, self::WRITE);
+        $file = $this->inputItem($id, self::WRITE);
 
         if (is_int($file)) {
             return $this->errorResponse($file);
         }
 
+
+        if ($parentHeader = $request->headers->get('X-Kolab-Parents', null)) {
+            $parents = explode(',', $parentHeader);
+            $file->parents()->sync($parents);
+        }
+        if ($parentHeader = $request->headers->get('X-Kolab-Add-Parents', null)) {
+            $parents = explode(',', $parentHeader);
+            $file->parents()->syncWithoutDetaching($parents);
+        }
+        if ($parentHeader = $request->headers->get('X-Kolab-Remove-Parents', null)) {
+            $parents = explode(',', $parentHeader);
+            $file->parents()->detach($parents);
+        }
+
         $media = $request->input('media') ?: 'metadata';
 
         if ($media == 'metadata') {
@@ -425,7 +536,7 @@
 
             // Validate file name input
             if ($filename != $file->getProperty('name')) {
-                $v = Validator::make($request->all(), ['name' => [new FileName($file->user)]]);
+                $v = Validator::make($request->all(), ['name' => [new FileName()]]);
 
                 if ($v->fails()) {
                     return response()->json(['status' => 'error', 'errors' => $v->errors()], 422);
@@ -548,7 +659,7 @@
      *
      * @return \App\Fs\Item|int File object or error code
      */
-    protected function inputFile($fileId, $permission)
+    protected function inputItem($fileId, $permission)
     {
         $user = $this->guard()->user();
         $isShare = str_starts_with($fileId, 'share-');
@@ -572,7 +683,7 @@
 
         $file = Item::find($fileId);
 
-        if (!$file || !($file->type & Item::TYPE_FILE) || ($file->type & Item::TYPE_INCOMPLETE)) {
+        if (!$file) {
             return 404;
         }
 
@@ -580,6 +691,10 @@
             return 403;
         }
 
+        if ($file->type & Item::TYPE_FILE &&  $file->type & Item::TYPE_INCOMPLETE) {
+            return 404;
+        }
+
         return $file;
     }
 
@@ -594,6 +709,11 @@
     protected function objectToClient($object, bool $full = false): array
     {
         $result = ['id' => $object->id];
+        if ($object->type & ITEM::TYPE_COLLECTION) {
+            $result['type'] = 'collection';
+        } else {
+            $result['type'] = 'item';
+        }
 
         if ($full) {
             $props = array_filter($object->getProperties(['name', 'size', 'mimetype']));
diff --git a/src/app/Providers/PassportServiceProvider.php b/src/app/Providers/PassportServiceProvider.php
--- a/src/app/Providers/PassportServiceProvider.php
+++ b/src/app/Providers/PassportServiceProvider.php
@@ -20,6 +20,7 @@
         Passport::tokensCan([
             'api' => 'Access API',
             'mfa' => 'Access MFA API',
+            'files' => 'Access Files API',
         ]);
 
         Passport::tokensExpireIn(now()->addMinutes(\config('auth.token_expiry_minutes')));
diff --git a/src/app/Rules/FileName.php b/src/app/Rules/FileName.php
--- a/src/app/Rules/FileName.php
+++ b/src/app/Rules/FileName.php
@@ -3,23 +3,10 @@
 namespace App\Rules;
 
 use Illuminate\Contracts\Validation\Rule;
-use Illuminate\Support\Facades\Validator;
-use Illuminate\Support\Str;
 
 class FileName implements Rule
 {
     private $message;
-    private $owner;
-
-    /**
-     * Class constructor.
-     *
-     * @param \App\User $owner  The file owner
-     */
-    public function __construct($owner)
-    {
-        $this->owner = $owner;
-    }
 
     /**
      * Determine if the validation rule passes.
@@ -56,18 +43,6 @@
 
         // FIXME: Should we require a dot?
 
-        // Check if the name is unique
-        $exists = $this->owner->fsItems()
-            ->join('fs_properties', 'fs_items.id', '=', 'fs_properties.item_id')
-            ->where('key', 'name')
-            ->where('value', $name)
-            ->exists();
-
-        if ($exists) {
-            $this->message = \trans('validation.file-name-exists');
-            return false;
-        }
-
         return true;
     }
 
diff --git a/src/database/migrations/2023_03_05_100000_fs_relations_table.php b/src/database/migrations/2023_03_05_100000_fs_relations_table.php
new file mode 100644
--- /dev/null
+++ b/src/database/migrations/2023_03_05_100000_fs_relations_table.php
@@ -0,0 +1,41 @@
+<?php
+
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Database\Migrations\Migration;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up(): void
+    {
+        Schema::create(
+            'fs_relations',
+            function (Blueprint $table) {
+                $table->bigIncrements('id');
+                $table->string('item', 36);
+                $table->string('related', 36);
+
+                $table->foreign('item')->references('id')->on('fs_items')
+                    ->onDelete('cascade');
+                $table->foreign('related')->references('id')->on('fs_items')
+                    ->onDelete('cascade');
+                $table->unique(['item', 'related']);
+            }
+        );
+    }
+
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('fs_relations');
+    }
+};
diff --git a/src/resources/js/files.js b/src/resources/js/files.js
--- a/src/resources/js/files.js
+++ b/src/resources/js/files.js
@@ -94,7 +94,7 @@
 
             // A "recursive" function to upload the file in chunks (if needed)
             const uploadFn = (start = 0, uploadId) => {
-                let url = 'api/v4/files'
+                let url = 'api/v4/items'
                 let body = ''
 
                 if (file.size <= maxChunkSize) {
@@ -103,15 +103,21 @@
                     // the file is uploading, but the risk is quite small.
                     body = file
                     start += maxChunkSize
+                    if (params.parent) {
+                        url = url + '?parent=' + params.parent
+                    }
                 } else if (!uploadId) {
                     // The file is big, first send a request for the upload location
                     // The upload location does not require authentication, which means
                     // there should be no problem with expired auth token, etc.
                     config.params.media = 'resumable'
                     config.params.size = file.size
+                    if (params.parent) {
+                        url = url + '?parent=' + params.parent
+                    }
                 } else {
                     // Upload a chunk of the file to the upload location
-                    url = 'api/v4/files/uploads/' + uploadId
+                    url = 'api/v4/items/uploads/' + uploadId
                     body = file.slice(start, start + maxChunkSize, file.type)
 
                     config.params = { from: start }
@@ -154,7 +160,7 @@
      * Download a file. Starts downloading using a hidden link trick.
      */
     this.fileDownload = (id) => {
-        axios.get('api/v4/files/' + id + '?downloadUrl=1')
+        axios.get('api/v4/items/' + id + '?downloadUrl=1')
             .then(response => {
                 // Create a dummy link element and click it
                 if (response.data.downloadUrl) {
@@ -167,7 +173,7 @@
      * Rename a file.
      */
     this.fileRename = (id, name) => {
-        axios.put('api/v4/files/' + id, { name })
+        axios.put('api/v4/items/' + id, { name })
             .then(response => {
 
             })
diff --git a/src/resources/js/user/routes.js b/src/resources/js/user/routes.js
--- a/src/resources/js/user/routes.js
+++ b/src/resources/js/user/routes.js
@@ -82,7 +82,7 @@
         meta: { requiresAuth: true /*, perm: 'files' */ }
     },
     {
-        path: '/files',
+        path: '/files/:parent?',
         name: 'files',
         component: FileListComponent,
         meta: { requiresAuth: true, perm: 'files' }
diff --git a/src/resources/lang/en/app.php b/src/resources/lang/en/app.php
--- a/src/resources/lang/en/app.php
+++ b/src/resources/lang/en/app.php
@@ -79,6 +79,10 @@
     'file-permissions-update-success' => 'File permissions updated successfully.',
     'file-permissions-delete-success' => 'File permissions deleted successfully.',
 
+    'collection-create-success' => 'Collection created successfully.',
+    'collection-delete-success' => 'Collection deleted successfully.',
+    'collection-update-success' => 'Collection updated successfully.',
+
     'payment-status-paid' => 'The payment has been completed successfully.',
     'payment-status-canceled' => 'The payment has been canceled.',
     'payment-status-failed' => 'The payment failed.',
diff --git a/src/resources/lang/en/ui.php b/src/resources/lang/en/ui.php
--- a/src/resources/lang/en/ui.php
+++ b/src/resources/lang/en/ui.php
@@ -162,6 +162,12 @@
             . "to the file via a unique link.",
     ],
 
+    'collection' => [
+        'create' => "Create collection",
+        'new' => "New Collection",
+        'name' => "Name",
+    ],
+
     'form' => [
         'acl' => "Access rights",
         'acl-full' => "All",
diff --git a/src/resources/vue/File/Info.vue b/src/resources/vue/File/Info.vue
--- a/src/resources/vue/File/Info.vue
+++ b/src/resources/vue/File/Info.vue
@@ -1,7 +1,21 @@
 <template>
     <div class="container">
         <div class="card" id="file-info">
-            <div class="card-body">
+            <div class="card-body" v-if="fileId === 'newCollection'">
+                <div class="card-title" >{{ $t('collection.new') }}</div>
+                <div class="card-text">
+                    <form @submit.prevent="submit" class="card-body">
+                        <div class="row mb-3">
+                            <label for="name" class="col-sm-4 col-form-label">{{ $t('collection.name') }}</label>
+                            <div class="col-sm-8">
+                                <input type="text" class="form-control" id="name" v-model="file.name" :disabled="file.id">
+                            </div>
+                        </div>
+                        <btn v-if="!file.id" class="btn-primary mt-3" type="submit" icon="check">{{ $t('btn.submit') }}</btn>
+                    </form>
+                </div>
+            </div>
+            <div class="card-body" v-else>
                 <div class="card-title">
                     {{ file.name }}
                     <btn v-if="file.canDelete" class="btn-outline-danger button-delete float-end" @click="fileDelete" icon="trash-can">{{ $t('file.delete') }}</btn>
@@ -83,6 +97,7 @@
             return {
                 file: {},
                 fileId: null,
+                collectionId: null,
                 shares: []
             }
         },
@@ -90,21 +105,24 @@
             this.api = new FileAPI({})
 
             this.fileId = this.$route.params.file
+            this.collectionId = this.$route.query.parent
 
-            axios.get('/api/v4/files/' + this.fileId, { loader: true })
-                .then(response => {
-                    this.file = response.data
+            if (this.fileId != 'newCollection') {
+                axios.get('/api/v4/files/' + this.fileId, { loader: true })
+                    .then(response => {
+                        this.file = response.data
 
-                    if (this.file.isOwner) {
-                        axios.get('api/v4/files/' + this.fileId + '/permissions')
-                            .then(response => {
-                                if (response.data.list) {
-                                    this.shares = response.data.list
-                                }
-                            })
-                    }
-                })
-                .catch(this.$root.errorHandler)
+                        if (this.file.isOwner) {
+                            axios.get('api/v4/files/' + this.fileId + '/permissions')
+                                .then(response => {
+                                    if (response.data.list) {
+                                        this.shares = response.data.list
+                                    }
+                                })
+                        }
+                    })
+                    .catch(this.$root.errorHandler)
+            }
         },
         methods: {
             copyLink(link) {
@@ -145,6 +163,19 @@
                             this.$delete(this.shares, this.shares.findIndex(element => element.id == id))
                         }
                     })
+            },
+            submit() {
+                this.$root.clearFormValidation($('#general form'))
+
+                let post = this.$root.pick(this.file, ['name'])
+                axios.post('/api/v4/items', post, { params: {
+                        type: 'collection',
+                        parent: this.collectionId
+                    }})
+                    .then(response => {
+                        this.$toast.success(response.data.message)
+                        this.$router.replace({ name: 'files', params: { parent: this.collectionId }})
+                    })
             }
         }
     }
diff --git a/src/resources/vue/File/List.vue b/src/resources/vue/File/List.vue
--- a/src/resources/vue/File/List.vue
+++ b/src/resources/vue/File/List.vue
@@ -2,12 +2,25 @@
     <div class="container">
         <div class="card" id="files">
             <div class="card-body">
-                <div class="card-title">
+                <div class="card-title" v-if="collectionId">
+                    {{ $t('dashboard.files') + ' - ' + collection.name }}
+                    <small><sup class="badge bg-primary">{{ $t('dashboard.beta') }}</sup></small>
+                    <div id="drop-area" class="file-drop-area float-end">
+                        <svg-icon icon="upload"></svg-icon> Click or drop file(s) here
+                    </div>
+                    <btn-router v-if="!$root.isDegraded()" class="float-end" :to="`/file/newCollection?parent=${collectionId}`" icon="folder">
+                        {{ $t('collection.create') }}
+                    </btn-router>
+                </div>
+                <div class="card-title" v-else>
                     {{ $t('dashboard.files') }}
                     <small><sup class="badge bg-primary">{{ $t('dashboard.beta') }}</sup></small>
                     <div id="drop-area" class="file-drop-area float-end">
                         <svg-icon icon="upload"></svg-icon> Click or drop file(s) here
                     </div>
+                    <btn-router v-if="!$root.isDegraded()" class="float-end" to="/file/newCollection" icon="folder">
+                        {{ $t('collection.create') }}
+                    </btn-router>
                 </div>
                 <div class="card-text pt-4">
                     <div class="mb-2 d-flex w-100">
@@ -22,11 +35,18 @@
                         </thead>
                         <tbody>
                             <tr v-for="file in files" :key="file.id" @click="$root.clickRecord">
-                                <td class="name">
+                                <td class="name" v-if="file.type === 'collection'">
+                                    <svg-icon icon="folder"></svg-icon>
+                                    <router-link :to="{ path: '/files/' + file.id }">{{ file.name }}</router-link>
+                                </td>
+                                <td class="name" v-else>
                                     <svg-icon icon="file"></svg-icon>
-                                    <router-link :to="{ path: 'file/' + file.id }">{{ file.name }}</router-link>
+                                    <router-link :to="{ path: '/file/' + file.id }">{{ file.name }}</router-link>
+                                </td>
+                                <td class="buttons" v-if="file.type === 'collection'">
+                                    <btn class="button-delete text-danger p-0 ms-1" @click="fileDelete(file)" icon="trash-can" :title="$t('btn.delete')"></btn>
                                 </td>
-                                <td class="buttons">
+                                <td class="buttons" v-else>
                                     <btn class="button-download p-0 ms-1" @click="fileDownload(file)" icon="download" :title="$t('btn.download')"></btn>
                                     <btn class="button-delete text-danger p-0 ms-1" @click="fileDelete(file)" icon="trash-can" :title="$t('btn.delete')"></btn>
                                 </td>
@@ -49,24 +69,47 @@
 
     library.add(
         require('@fortawesome/free-solid-svg-icons/faFile').definition,
+        require('@fortawesome/free-solid-svg-icons/faFolder').definition,
         require('@fortawesome/free-solid-svg-icons/faDownload').definition,
         require('@fortawesome/free-solid-svg-icons/faUpload').definition,
     )
 
     export default {
         mixins: [ ListTools ],
+        beforeRouteUpdate (to, from, next) {
+            this.collectionId = this.$route.params.parent
+            // An event called when the route that renders this component has changed,
+            // but this component is reused in the new route.
+            // Required to handle links from /file/XXX to /file/YYY
+            next()
+            this.$parent.routerReload()
+        },
         data() {
             return {
                 api: {},
-                files: []
+                collection: {},
+                files: [],
+                collectionId: null
+            }
+        },
+        created() {
+            this.collectionId = this.$route.params.parent
+            if (this.collectionId) {
+                axios.get('/api/v4/items/' + this.collectionId, { loader: true })
+                    .then(response => {
+                        this.collection = response.data
+                    })
+                    .catch(this.$root.errorHandler)
             }
         },
         mounted() {
             this.uploads = {}
 
+            this.collectionId = this.$route.params.parent
             this.api = new FileAPI({
                     dropArea: '#drop-area',
-                    eventHandler: this.eventHandler
+                    eventHandler: this.eventHandler,
+                    parent: this.collectionId
             })
 
             this.loadFiles({ init: true })
@@ -81,7 +124,7 @@
                 }
             },
             fileDelete(file) {
-                axios.delete('api/v4/files/' + file.id)
+                axios.delete('api/v4/items/' + file.id)
                     .then(response => {
                         if (response.data.status == 'success') {
                             this.$toast.success(response.data.message)
@@ -100,7 +143,10 @@
                 this.api.fileDownload(file.id)
             },
             loadFiles(params) {
-                this.listSearch('files', 'api/v4/files', params)
+                if (this.collectionId) {
+                    params['parent'] = this.collectionId
+                }
+                this.listSearch('files', 'api/v4/items', params)
             },
             searchFiles(search) {
                 this.loadFiles({ reset: true, search })
diff --git a/src/resources/vue/Widgets/ListTools.vue b/src/resources/vue/Widgets/ListTools.vue
--- a/src/resources/vue/Widgets/ListTools.vue
+++ b/src/resources/vue/Widgets/ListTools.vue
@@ -99,6 +99,7 @@
         data() {
             return {
                 currentSearch: '',
+                currentParent: '',
                 hasMore: false,
                 page: 1
             }
@@ -124,6 +125,14 @@
                         get.search = this.currentSearch
                     }
 
+
+                    if ('parent' in params) {
+                        get.parent = params.parent
+                        this.currentParent = params.parent
+                    } else {
+                        get.parent = this.currentParent
+                    }
+
                     if (!params.init) {
                         loader = $(this.$el).find('.more-loader')
                         if (!loader.length || get.page == 1) {
@@ -134,6 +143,7 @@
                     }
                 } else {
                     this.currentSearch = null
+                    this.currentParent = null
                 }
 
                 axios.get(url, { params: get, loader })
diff --git a/src/routes/api.php b/src/routes/api.php
--- a/src/routes/api.php
+++ b/src/routes/api.php
@@ -75,6 +75,44 @@
     }
 );
 
+if (\config('app.with_files')) {
+    Route::group(
+        [
+            'domain' => \config('app.website_domain'),
+            'middleware' => ['auth:api', 'scope:files,api'],
+            'prefix' => 'v4'
+        ],
+        function () {
+                Route::apiResource('files', API\V4\FsController::class);
+                Route::post('collections', [API\V4\FsController::class, 'createCollection']);
+                Route::get('files/{fileId}/permissions', [API\V4\FsController::class, 'getPermissions']);
+                Route::post('files/{fileId}/permissions', [API\V4\FsController::class, 'createPermission']);
+                Route::put('files/{fileId}/permissions/{id}', [API\V4\FsController::class, 'updatePermission']);
+                Route::delete('files/{fileId}/permissions/{id}', [API\V4\FsController::class, 'deletePermission']);
+                Route::apiResource('items', API\V4\FsController::class);
+                Route::get('items/{itemId}/permissions', [API\V4\FsController::class, 'getPermissions']);
+                Route::post('items/{itemId}/permissions', [API\V4\FsController::class, 'createPermission']);
+                Route::put('items/{itemId}/permissions/{id}', [API\V4\FsController::class, 'updatePermission']);
+                Route::delete('items/{itemId}/permissions/{id}', [API\V4\FsController::class, 'deletePermission']);
+        }
+    );
+    Route::group(
+        [
+            'domain' => \config('app.website_domain'),
+            'middleware' => [],
+            'prefix' => 'v4'
+        ],
+        function () {
+                Route::post('files/uploads/{id}', [API\V4\FsController::class, 'upload'])
+                    ->middleware(['api']);
+                Route::get('files/downloads/{id}', [API\V4\FsController::class, 'download']);
+                Route::post('items/uploads/{id}', [API\V4\FsController::class, 'upload'])
+                    ->middleware(['api']);
+                Route::get('items/downloads/{id}', [API\V4\FsController::class, 'download']);
+        }
+    );
+}
+
 Route::group(
     [
         'domain' => \config('app.website_domain'),
@@ -93,19 +131,6 @@
         Route::get('domains/{id}/status', [API\V4\DomainsController::class, 'status']);
         Route::post('domains/{id}/config', [API\V4\DomainsController::class, 'setConfig']);
 
-        if (\config('app.with_files')) {
-            Route::apiResource('files', API\V4\FilesController::class);
-            Route::get('files/{fileId}/permissions', [API\V4\FilesController::class, 'getPermissions']);
-            Route::post('files/{fileId}/permissions', [API\V4\FilesController::class, 'createPermission']);
-            Route::put('files/{fileId}/permissions/{id}', [API\V4\FilesController::class, 'updatePermission']);
-            Route::delete('files/{fileId}/permissions/{id}', [API\V4\FilesController::class, 'deletePermission']);
-            Route::post('files/uploads/{id}', [API\V4\FilesController::class, 'upload'])
-                ->withoutMiddleware(['auth:api', 'scope:api'])
-                ->middleware(['api']);
-            Route::get('files/downloads/{id}', [API\V4\FilesController::class, 'download'])
-                ->withoutMiddleware(['auth:api', 'scope:api']);
-        }
-
         Route::apiResource('groups', API\V4\GroupsController::class);
         Route::get('groups/{id}/skus', [API\V4\GroupsController::class, 'skus']);
         Route::get('groups/{id}/status', [API\V4\GroupsController::class, 'status']);
diff --git a/src/tests/Feature/Controller/FilesTest.php b/src/tests/Feature/Controller/FsTest.php
rename from src/tests/Feature/Controller/FilesTest.php
rename to src/tests/Feature/Controller/FsTest.php
--- a/src/tests/Feature/Controller/FilesTest.php
+++ b/src/tests/Feature/Controller/FsTest.php
@@ -12,7 +12,7 @@
 /**
  * @group files
  */
-class FilesTest extends TestCase
+class FsTest extends TestCase
 {
     /**
      * {@inheritDoc}
@@ -31,7 +31,7 @@
     {
         Item::query()->delete();
 
-        $disk = LaravelStorage::disk('files');
+        $disk = LaravelStorage::disk(\config('filesystems.default'));
         foreach ($disk->listContents('') as $dir) {
             $disk->deleteDirectory($dir->path());
         }
@@ -40,7 +40,7 @@
     }
 
     /**
-     * Test deleting files (DELETE /api/v4/files/<file-id>)
+     * Test deleting items (DELETE /api/v4/items/<item-id>)
      */
     public function testDelete(): void
     {
@@ -49,19 +49,19 @@
         $file = $this->getTestFile($john, 'teśt.txt', 'Teśt content', ['mimetype' => 'plain/text']);
 
         // Unauth access
-        $response = $this->delete("api/v4/files/{$file->id}");
+        $response = $this->delete("api/v4/items/{$file->id}");
         $response->assertStatus(401);
 
         // Unauth access
-        $response = $this->actingAs($jack)->delete("api/v4/files/{$file->id}");
+        $response = $this->actingAs($jack)->delete("api/v4/items/{$file->id}");
         $response->assertStatus(403);
 
         // Non-existing file
-        $response = $this->actingAs($john)->delete("api/v4/files/123");
+        $response = $this->actingAs($john)->delete("api/v4/items/123");
         $response->assertStatus(404);
 
         // File owner access
-        $response = $this->actingAs($john)->delete("api/v4/files/{$file->id}");
+        $response = $this->actingAs($john)->delete("api/v4/items/{$file->id}");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -70,13 +70,13 @@
         $this->assertSame("File deleted successfully.", $json['message']);
         $this->assertSame(null, Item::find($file->id));
 
-        // Note: The file is expected to stay still in the filesystem, we're not testing this here.
+        // Note: The file is expected to stay still in the itemsystem, we're not testing this here.
 
         // TODO: Test acting as another user with permissions
     }
 
     /**
-     * Test file downloads (GET /api/v4/files/downloads/<id>)
+     * Test file downloads (GET /api/v4/items/downloads/<id>)
      */
     public function testDownload(): void
     {
@@ -85,18 +85,18 @@
         $file = $this->getTestFile($john, 'teśt.txt', 'Teśt content', ['mimetype' => 'plain/text']);
 
         // Unauth access
-        $response = $this->get("api/v4/files/{$file->id}?downloadUrl=1");
+        $response = $this->get("api/v4/items/{$file->id}?downloadUrl=1");
         $response->assertStatus(401);
 
-        $response = $this->actingAs($jack)->get("api/v4/files/{$file->id}?downloadUrl=1");
+        $response = $this->actingAs($jack)->get("api/v4/items/{$file->id}?downloadUrl=1");
         $response->assertStatus(403);
 
         // Non-existing file
-        $response = $this->actingAs($john)->get("api/v4/files/123456?downloadUrl=1");
+        $response = $this->actingAs($john)->get("api/v4/items/123456?downloadUrl=1");
         $response->assertStatus(404);
 
         // Get downloadLink for the file
-        $response = $this->actingAs($john)->get("api/v4/files/{$file->id}?downloadUrl=1");
+        $response = $this->actingAs($john)->get("api/v4/items/{$file->id}?downloadUrl=1");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -108,14 +108,13 @@
         $response = $this->get(substr($link, strpos($link, '/api/') + 1));
         $response->assertStatus(200)
             ->assertHeader('Content-Disposition', "attachment; filename=test.txt; filename*=utf-8''te%C5%9Bt.txt")
-            ->assertHeader('Content-Length', $file->getProperty('size'))
             ->assertHeader('Content-Type', $file->getProperty('mimetype'));
 
         $this->assertSame('Teśt content', $response->streamedContent());
 
         // Test acting as another user with read permission
         $permission = $this->getTestFilePermission($file, $jack, 'r');
-        $response = $this->actingAs($jack)->get("api/v4/files/{$permission->key}?downloadUrl=1");
+        $response = $this->actingAs($jack)->get("api/v4/items/{$permission->key}?downloadUrl=1");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -127,14 +126,13 @@
         $response = $this->get(substr($link, strpos($link, '/api/') + 1));
         $response->assertStatus(200)
             ->assertHeader('Content-Disposition', "attachment; filename=test.txt; filename*=utf-8''te%C5%9Bt.txt")
-            ->assertHeader('Content-Length', $file->getProperty('size'))
             ->assertHeader('Content-Type', $file->getProperty('mimetype'));
 
         $this->assertSame('Teśt content', $response->streamedContent());
 
         // Test downloading a multi-chunk file
         $file = $this->getTestFile($john, 'test2.txt', ['T1', 'T2'], ['mimetype' => 'plain/text']);
-        $response = $this->actingAs($john)->get("api/v4/files/{$file->id}?downloadUrl=1");
+        $response = $this->actingAs($john)->get("api/v4/items/{$file->id}?downloadUrl=1");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -146,14 +144,13 @@
         $response = $this->get(substr($link, strpos($link, '/api/') + 1));
         $response->assertStatus(200)
             ->assertHeader('Content-Disposition', "attachment; filename=test2.txt")
-            ->assertHeader('Content-Length', $file->getProperty('size'))
             ->assertHeader('Content-Type', $file->getProperty('mimetype'));
 
         $this->assertSame('T1T2', $response->streamedContent());
     }
 
     /**
-     * Test fetching/creating/updaing/deleting file permissions (GET|POST|PUT /api/v4/files/<file-id>/permissions)
+     * Test fetching/creating/updaing/deleting file permissions (GET|POST|PUT /api/v4/items/<file-id>/permissions)
      */
     public function testPermissions(): void
     {
@@ -162,25 +159,25 @@
         $file = $this->getTestFile($john, 'test1.txt', []);
 
         // Unauth access not allowed
-        $response = $this->get("api/v4/files/{$file->id}/permissions");
+        $response = $this->get("api/v4/items/{$file->id}/permissions");
         $response->assertStatus(401);
-        $response = $this->post("api/v4/files/{$file->id}/permissions", []);
+        $response = $this->post("api/v4/items/{$file->id}/permissions", []);
         $response->assertStatus(401);
 
         // Non-existing file
-        $response = $this->actingAs($john)->get("api/v4/files/1234/permissions");
+        $response = $this->actingAs($john)->get("api/v4/items/1234/permissions");
         $response->assertStatus(404);
-        $response = $this->actingAs($john)->post("api/v4/files/1234/permissions", []);
+        $response = $this->actingAs($john)->post("api/v4/items/1234/permissions", []);
         $response->assertStatus(404);
 
         // No permissions to the file
-        $response = $this->actingAs($jack)->get("api/v4/files/{$file->id}/permissions");
+        $response = $this->actingAs($jack)->get("api/v4/items/{$file->id}/permissions");
         $response->assertStatus(403);
-        $response = $this->actingAs($jack)->post("api/v4/files/{$file->id}/permissions", []);
+        $response = $this->actingAs($jack)->post("api/v4/items/{$file->id}/permissions", []);
         $response->assertStatus(403);
 
         // Expect an empty list of permissions
-        $response = $this->actingAs($john)->get("api/v4/files/{$file->id}/permissions");
+        $response = $this->actingAs($john)->get("api/v4/items/{$file->id}/permissions");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -190,7 +187,7 @@
         $this->assertSame(0, $json['count']);
 
         // Empty input
-        $response = $this->actingAs($john)->post("api/v4/files/{$file->id}/permissions", []);
+        $response = $this->actingAs($john)->post("api/v4/items/{$file->id}/permissions", []);
         $response->assertStatus(422);
 
         $json = $response->json();
@@ -202,7 +199,7 @@
 
         // Test more input validation
         $post = ['user' => 'user', 'permissions' => 'read'];
-        $response = $this->actingAs($john)->post("api/v4/files/{$file->id}/permissions", $post);
+        $response = $this->actingAs($john)->post("api/v4/items/{$file->id}/permissions", $post);
         $response->assertStatus(422);
 
         $json = $response->json();
@@ -214,7 +211,7 @@
 
         // Let's add some permission
         $post = ['user' => 'jack@kolab.org', 'permissions' => 'read-only'];
-        $response = $this->actingAs($john)->post("api/v4/files/{$file->id}/permissions", $post);
+        $response = $this->actingAs($john)->post("api/v4/items/{$file->id}/permissions", $post);
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -232,7 +229,7 @@
 
         // Error handling on use of the same user
         $post = ['user' => 'jack@kolab.org', 'permissions' => 'read-only'];
-        $response = $this->actingAs($john)->post("api/v4/files/{$file->id}/permissions", $post);
+        $response = $this->actingAs($john)->post("api/v4/items/{$file->id}/permissions", $post);
         $response->assertStatus(422);
 
         $json = $response->json();
@@ -241,11 +238,11 @@
         $this->assertSame("File permission already exists.", $json['errors']['user']);
 
         // Test update
-        $response = $this->actingAs($john)->put("api/v4/files/{$file->id}/permissions/1234", $post);
+        $response = $this->actingAs($john)->put("api/v4/items/{$file->id}/permissions/1234", $post);
         $response->assertStatus(404);
 
         $post = ['user' => 'jack@kolab.org', 'permissions' => 'read-write'];
-        $response = $this->actingAs($john)->put("api/v4/files/{$file->id}/permissions/{$permission->key}", $post);
+        $response = $this->actingAs($john)->put("api/v4/items/{$file->id}/permissions/{$permission->key}", $post);
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -263,7 +260,7 @@
 
         // Input validation on update
         $post = ['user' => 'jack@kolab.org', 'permissions' => 'read'];
-        $response = $this->actingAs($john)->put("api/v4/files/{$file->id}/permissions/{$permission->key}", $post);
+        $response = $this->actingAs($john)->put("api/v4/items/{$file->id}/permissions/{$permission->key}", $post);
         $response->assertStatus(422);
 
         $json = $response->json();
@@ -272,7 +269,7 @@
         $this->assertSame("The file permission is invalid.", $json['errors']['permissions']);
 
         // Test GET with existing permissions
-        $response = $this->actingAs($john)->get("api/v4/files/{$file->id}/permissions");
+        $response = $this->actingAs($john)->get("api/v4/items/{$file->id}/permissions");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -287,10 +284,10 @@
         $this->assertSame(\App\Utils::serviceUrl('file/' . $permission->key), $json['list'][0]['link']);
 
         // Delete permission
-        $response = $this->actingAs($john)->delete("api/v4/files/{$file->id}/permissions/1234");
+        $response = $this->actingAs($john)->delete("api/v4/items/{$file->id}/permissions/1234");
         $response->assertStatus(404);
 
-        $response = $this->actingAs($john)->delete("api/v4/files/{$file->id}/permissions/{$permission->key}");
+        $response = $this->actingAs($john)->delete("api/v4/items/{$file->id}/permissions/{$permission->key}");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -302,18 +299,18 @@
     }
 
     /**
-     * Test fetching files/folders list (GET /api/v4/files)
+     * Test fetching items/folders list (GET /api/v4/items)
      */
     public function testIndex(): void
     {
         // Unauth access not allowed
-        $response = $this->get("api/v4/files");
+        $response = $this->get("api/v4/items");
         $response->assertStatus(401);
 
         $user = $this->getTestUser('john@kolab.org');
 
         // Expect an empty list
-        $response = $this->actingAs($user)->get("api/v4/files");
+        $response = $this->actingAs($user)->get("api/v4/items");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -323,11 +320,11 @@
         $this->assertSame(0, $json['count']);
         $this->assertSame(false, $json['hasMore']);
 
-        // Create some files and test again
+        // Create some items and test again
         $file1 = $this->getTestFile($user, 'test1.txt', [], ['mimetype' => 'text/plain', 'size' => 12345]);
         $file2 = $this->getTestFile($user, 'test2.gif', [], ['mimetype' => 'image/gif', 'size' => 10000]);
 
-        $response = $this->actingAs($user)->get("api/v4/files");
+        $response = $this->actingAs($user)->get("api/v4/items");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -342,7 +339,7 @@
         $this->assertSame($file2->id, $json['list'][1]['id']);
 
         // Searching
-        $response = $this->actingAs($user)->get("api/v4/files?search=t2");
+        $response = $this->actingAs($user)->get("api/v4/items?search=t2");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -356,11 +353,11 @@
 
         // TODO: Test paging
 
-        // Make sure incomplete files are skipped
+        // Make sure incomplete items are skipped
         $file1->type |= Item::TYPE_INCOMPLETE;
         $file1->save();
 
-        $response = $this->actingAs($user)->get("api/v4/files");
+        $response = $this->actingAs($user)->get("api/v4/items");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -370,12 +367,12 @@
     }
 
     /**
-     * Test fetching file metadata (GET /api/v4/files/<file-id>)
+     * Test fetching file metadata (GET /api/v4/items/<file-id>)
      */
     public function testShow(): void
     {
         // Unauth access not allowed
-        $response = $this->get("api/v4/files/1234");
+        $response = $this->get("api/v4/items/1234");
         $response->assertStatus(401);
 
         $john = $this->getTestUser('john@kolab.org');
@@ -383,15 +380,15 @@
         $file = $this->getTestFile($john, 'teśt.txt', 'Teśt content', ['mimetype' => 'plain/text']);
 
         // Non-existing file
-        $response = $this->actingAs($jack)->get("api/v4/files/1234");
+        $response = $this->actingAs($jack)->get("api/v4/items/1234");
         $response->assertStatus(404);
 
         // Unauthorized access
-        $response = $this->actingAs($jack)->get("api/v4/files/{$file->id}");
+        $response = $this->actingAs($jack)->get("api/v4/items/{$file->id}");
         $response->assertStatus(403);
 
         // Get file metadata
-        $response = $this->actingAs($john)->get("api/v4/files/{$file->id}");
+        $response = $this->actingAs($john)->get("api/v4/items/{$file->id}");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -405,17 +402,16 @@
         $this->assertSame(true, $json['canDelete']);
 
         // Get file content
-        $response = $this->actingAs($john)->get("api/v4/files/{$file->id}?download=1");
+        $response = $this->actingAs($john)->get("api/v4/items/{$file->id}?download=1");
         $response->assertStatus(200)
             ->assertHeader('Content-Disposition', "attachment; filename=test.txt; filename*=utf-8''te%C5%9Bt.txt")
-            ->assertHeader('Content-Length', $file->getProperty('size'))
             ->assertHeader('Content-Type', $file->getProperty('mimetype'));
 
         $this->assertSame('Teśt content', $response->streamedContent());
 
         // Test acting as a user with file permissions
         $permission = $this->getTestFilePermission($file, $jack, 'r');
-        $response = $this->actingAs($jack)->get("api/v4/files/{$permission->key}");
+        $response = $this->actingAs($jack)->get("api/v4/items/{$permission->key}");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -427,18 +423,18 @@
     }
 
     /**
-     * Test creating files (POST /api/v4/files)
+     * Test creating items (POST /api/v4/items)
      */
     public function testStore(): void
     {
         // Unauth access not allowed
-        $response = $this->post("api/v4/files");
+        $response = $this->post("api/v4/items");
         $response->assertStatus(401);
 
         $john = $this->getTestUser('john@kolab.org');
 
         // Test input validation
-        $response = $this->sendRawBody($john, 'POST', "api/v4/files", [], '');
+        $response = $this->sendRawBody($john, 'POST', "api/v4/items", [], '');
         $response->assertStatus(422);
 
         $json = $response->json();
@@ -446,7 +442,7 @@
         $this->assertSame('error', $json['status']);
         $this->assertSame(["The name field is required."], $json['errors']['name']);
 
-        $response = $this->sendRawBody($john, 'POST', "api/v4/files?name=*.txt", [], '');
+        $response = $this->sendRawBody($john, 'POST', "api/v4/items?name=*.txt", [], '');
         $response->assertStatus(422);
 
         $json = $response->json();
@@ -457,7 +453,7 @@
         // Create a file - the simple method
         $body = "test content";
         $headers = [];
-        $response = $this->sendRawBody($john, 'POST', "api/v4/files?name=test.txt", $headers, $body);
+        $response = $this->sendRawBody($john, 'POST', "api/v4/items?name=test.txt", $headers, $body);
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -478,13 +474,13 @@
     }
 
     /**
-     * Test creating files - resumable (POST /api/v4/files)
+     * Test creating items - resumable (POST /api/v4/items)
      */
     public function testStoreResumable(): void
     {
         $john = $this->getTestUser('john@kolab.org');
 
-        $response = $this->actingAs($john)->post("api/v4/files?name=test2.txt&media=resumable&size=400");
+        $response = $this->actingAs($john)->post("api/v4/items?name=test2.txt&media=resumable&size=400");
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -501,7 +497,7 @@
 
         for ($x = 0; $x <= 2; $x++) {
             $body = str_repeat("$x", 100);
-            $response = $this->sendRawBody(null, 'POST', "api/v4/files/uploads/{$uploadId}?from={$size}", [], $body);
+            $response = $this->sendRawBody(null, 'POST', "api/v4/items/uploads/{$uploadId}?from={$size}", [], $body);
             $response->assertStatus(200);
 
             $json = $response->json();
@@ -513,7 +509,7 @@
         }
 
         $body = str_repeat("$x", 100);
-        $response = $this->sendRawBody(null, 'POST', "api/v4/files/uploads/{$uploadId}?from={$size}", [], $body);
+        $response = $this->sendRawBody(null, 'POST', "api/v4/items/uploads/{$uploadId}?from={$size}", [], $body);
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -536,12 +532,12 @@
     }
 
     /**
-     * Test updating files (PUT /api/v4/files/<file-id>)
+     * Test updating items (PUT /api/v4/items/<file-id>)
      */
     public function testUpdate(): void
     {
         // Unauth access not allowed
-        $response = $this->put("api/v4/files/1234");
+        $response = $this->put("api/v4/items/1234");
         $response->assertStatus(401);
 
         $john = $this->getTestUser('john@kolab.org');
@@ -549,16 +545,16 @@
         $file = $this->getTestFile($john, 'teśt.txt', 'Teśt content', ['mimetype' => 'plain/text']);
 
         // Non-existing file
-        $response = $this->actingAs($john)->put("api/v4/files/1234", []);
+        $response = $this->actingAs($john)->put("api/v4/items/1234", []);
         $response->assertStatus(404);
 
         // Unauthorized access
-        $response = $this->actingAs($jack)->put("api/v4/files/{$file->id}", []);
+        $response = $this->actingAs($jack)->put("api/v4/items/{$file->id}", []);
         $response->assertStatus(403);
 
         // Test name validation
         $post = ['name' => 'test/test.txt'];
-        $response = $this->actingAs($john)->put("api/v4/files/{$file->id}", $post);
+        $response = $this->actingAs($john)->put("api/v4/items/{$file->id}", $post);
         $response->assertStatus(422);
 
         $json = $response->json();
@@ -567,7 +563,7 @@
         $this->assertSame(["The file name is invalid."], $json['errors']['name']);
 
         $post = ['name' => 'new name.txt', 'media' => 'test'];
-        $response = $this->actingAs($john)->put("api/v4/files/{$file->id}", $post);
+        $response = $this->actingAs($john)->put("api/v4/items/{$file->id}", $post);
         $response->assertStatus(422);
 
         $json = $response->json();
@@ -577,7 +573,7 @@
 
         // Rename a file
         $post = ['name' => 'new namś.txt'];
-        $response = $this->actingAs($john)->put("api/v4/files/{$file->id}", $post);
+        $response = $this->actingAs($john)->put("api/v4/items/{$file->id}", $post);
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -591,7 +587,7 @@
 
         // Update file content
         $body = "Test1\nTest2";
-        $response = $this->sendRawBody($john, 'PUT', "api/v4/files/{$file->id}?media=content", [], $body);
+        $response = $this->sendRawBody($john, 'PUT', "api/v4/items/{$file->id}?media=content", [], $body);
         $response->assertStatus(200);
 
         $json = $response->json();
@@ -621,7 +617,7 @@
      */
     protected function getTestFile(User $user, string $name, $content = [], $props = []): Item
     {
-        $disk = LaravelStorage::disk('files');
+        $disk = LaravelStorage::disk(\config('filesystems.default'));
 
         $file = $user->fsItems()->create(['type' => Item::TYPE_FILE]);
         $size = 0;
@@ -656,6 +652,28 @@
         return $file;
     }
 
+    /**
+     * Create a test collection.
+     *
+     * @param \App\User    $user    File owner
+     * @param string       $name    File name
+     * @param array        $props   Extra collection properties
+     *
+     * @return \App\Fs\Item
+     */
+    protected function getTestCollection(User $user, string $name, $props = []): Item
+    {
+        $collection = $user->fsItems()->create(['type' => Item::TYPE_COLLECTION]);
+
+        $properties = [
+            'name' => $name,
+        ];
+
+        $collection->setProperties($props + $properties);
+
+        return $collection;
+    }
+
     /**
      * Get contents of a test file.
      *
@@ -668,7 +686,7 @@
         $content = '';
 
         $file->chunks()->orderBy('sequence')->get()->each(function ($chunk) use ($file, &$content) {
-            $disk = LaravelStorage::disk('files');
+            $disk = LaravelStorage::disk(\config('filesystems.default'));
             $path = Storage::chunkLocation($chunk->chunk_id, $file);
 
             $content .= $disk->read($path);
@@ -721,4 +739,237 @@
             return $this->call($method, $uri, [], $cookies, [], $server, $content);
         }
     }
+
+
+    /**
+     * Test creating collections (POST /api/v4/items?type=collection)
+     */
+    public function testStoreCollection(): void
+    {
+        $john = $this->getTestUser('john@kolab.org');
+
+        $params = [
+            'name' => "MyTestCollection",
+            'deviceId' => "myDeviceId",
+        ];
+        $response = $this->actingAs($john)->post("api/v4/items?type=collection", $params);
+
+        $response->assertStatus(200);
+
+        $json = $response->json();
+
+        $this->assertSame('success', $json['status']);
+
+        $collection = Item::find($json['id']);
+
+        $this->assertSame(Item::TYPE_COLLECTION, $collection->type);
+        $this->assertSame($params['name'], $collection->getProperty('name'));
+        $this->assertSame($params['deviceId'], $collection->getProperty('deviceId'));
+    }
+
+    /**
+     * Test creating collections (POST /api/v4/items?type=collection)
+     */
+    public function testStoreCollectionMetadata(): void
+    {
+        $john = $this->getTestUser('john@kolab.org');
+
+        $params = [
+            'name' => "MyTestCollection",
+            'deviceId' => "myDeviceId",
+            'collectionType' => "photoalbum",
+            'deduplicate-property' => "localId",
+            'deduplicate-value' => "myDeviceId:localId",
+            'property-localId' => "myDeviceId:localId",
+        ];
+        $response = $this->actingAs($john)->post("api/v4/items?type=collection", $params);
+
+        $response->assertStatus(200);
+
+        $json = $response->json();
+
+        $this->assertSame('success', $json['status']);
+
+        $collection = Item::find($json['id']);
+
+        $this->assertSame(Item::TYPE_COLLECTION, $collection->type);
+        $this->assertSame($params['name'], $collection->getProperty('name'));
+        $this->assertSame($params['deviceId'], $collection->getProperty('deviceId'));
+        $this->assertSame($params['collectionType'], $collection->getProperty('collectionType'));
+        $this->assertSame($params['property-localId'], $collection->getProperty('localId'));
+
+        // Deduplicate but update the name and parent
+        $parent = $this->getTestCollection($john, 'Parent');
+        $params = [
+            'name' => "MyTestCollection2",
+            'deviceId' => "myDeviceId",
+            'parent' => $parent->id,
+            'collectionType' => "photoalbum",
+            'deduplicate-property' => "localId",
+            'deduplicate-value' => "myDeviceId:localId",
+        ];
+        $response = $this->actingAs($john)->post("api/v4/items?type=collection", $params);
+
+        $response->assertStatus(200);
+
+        $json = $response->json();
+
+        $this->assertSame('success', $json['status']);
+        $this->assertSame($collection->id, $json['id']);
+        $this->assertSame($params['name'], $collection->getProperty('name'));
+
+
+        // Deduplicate again, but without changes
+        $parent = $this->getTestCollection($john, 'Parent');
+        $response = $this->actingAs($john)->post("api/v4/items?type=collection", $params);
+        $response->assertStatus(200);
+
+        $json = $response->json();
+        $this->assertSame('success', $json['status']);
+    }
+
+    /**
+     * Test deleting items (DELETE /api/v4/collections/<collection-id>)
+     */
+    public function testDeleteCollection(): void
+    {
+        $john = $this->getTestUser('john@kolab.org');
+        $collection = $this->getTestCollection($john, 'Teśt content');
+
+        // File owner access
+        $response = $this->actingAs($john)->delete("api/v4/items/{$collection->id}");
+        $response->assertStatus(200);
+
+        $json = $response->json();
+
+        $this->assertSame('success', $json['status']);
+        $this->assertSame("Collection deleted successfully.", $json['message']);
+        $this->assertSame(null, Item::find($collection->id));
+    }
+
+    /**
+     * Test store item relations (POST /api/v4/items)
+     */
+    public function testStoreRelation(): void
+    {
+        $john = $this->getTestUser('john@kolab.org');
+        $collection = $this->getTestCollection($john, 'My Test Collection');
+
+        $body = "test content";
+        $headers = ["X-Kolab-Parents" => implode(',', [$collection->id])];
+        $response = $this->sendRawBody($john, 'POST', "api/v4/items?name=test.txt", $headers, $body);
+        $response->assertStatus(200);
+
+        $json = $response->json();
+        $newItem = Item::find($json['id']);
+        $this->assertNotNull($newItem);
+        $this->assertSame(1, $newItem->parents()->count());
+        $this->assertSame($collection->id, $newItem->parents()->first()->id);
+
+
+        $collection2 = $this->getTestCollection($john, 'My Test Collection2');
+        $headers = ["X-Kolab-Parents" => implode(',', [$collection->id, $collection2->id])];
+        $response = $this->sendRawBody($john, 'POST', "api/v4/items?name=test2.txt", $headers, $body);
+        $response->assertStatus(200);
+
+        $json = $response->json();
+        $newItem = Item::find($json['id']);
+        $this->assertNotNull($newItem);
+        $this->assertSame(2, $newItem->parents()->count());
+    }
+
+    /**
+     * Test store item relations (POST /api/v4/items)
+     */
+    public function testStoreRelationParameter(): void
+    {
+        $john = $this->getTestUser('john@kolab.org');
+        $collection = $this->getTestCollection($john, 'My Test Collection');
+
+        $body = "test content";
+        $response = $this->sendRawBody($john, 'POST', "api/v4/items?name=test.txt&parent={$collection->id}", [], $body);
+        $response->assertStatus(200);
+
+        $json = $response->json();
+        $newItem = Item::find($json['id']);
+        $this->assertNotNull($newItem);
+        $this->assertSame(1, $newItem->parents()->count());
+        $this->assertSame($collection->id, $newItem->parents()->first()->id);
+    }
+
+    /**
+     * Test update item relations (PUT /api/v4/items/$itemid)
+     * Add/Remove/Set
+     */
+    public function testUpdateRelation(): void
+    {
+        $john = $this->getTestUser('john@kolab.org');
+        $file = $this->getTestFile($john, 'test1.txt', 'Teśt content1', ['mimetype' => 'plain/text']);
+        $collection1 = $this->getTestCollection($john, 'My Test Collection');
+        $collection2 = $this->getTestCollection($john, 'My Test Collection2');
+
+        // Add parents
+        $headers = ["X-Kolab-Add-Parents" => implode(',', [$collection1->id])];
+        $response = $this->sendRawBody($john, 'PUT', "api/v4/items/{$file->id}", $headers, '');
+        $response->assertStatus(200);
+        $this->assertSame('success', $response->json()['status']);
+
+        $parents = $file->parents()->get();
+        $this->assertSame(1, count($parents));
+        $this->assertSame($collection1->id, $parents->first()->id);
+
+        // Set parents
+        $headers = ["X-Kolab-Parents" => implode(',', [$collection1->id, $collection2->id])];
+        $response = $this->sendRawBody($john, 'PUT', "api/v4/items/{$file->id}", $headers, '');
+        $response->assertStatus(200);
+        $this->assertSame('success', $response->json()['status']);
+
+        $parents = $file->parents()->get();
+        $this->assertSame(2, count($parents));
+
+        // Remove parents
+        $headers = ["X-Kolab-Remove-Parents" => implode(',', [$collection1->id])];
+        $response = $this->sendRawBody($john, 'PUT', "api/v4/items/{$file->id}", $headers, '');
+        $response->assertStatus(200);
+        $this->assertSame('success', $response->json()['status']);
+
+        $parents = $file->parents()->get();
+        $this->assertSame(1, count($parents));
+        $this->assertSame($collection2->id, $parents->first()->id);
+    }
+
+    public function testListChildren(): void
+    {
+        $john = $this->getTestUser('john@kolab.org');
+        $file1 = $this->getTestFile($john, 'test1.txt', 'Teśt content1', ['mimetype' => 'plain/text']);
+        $file2 = $this->getTestFile($john, 'test2.txt', 'Teśt content2', ['mimetype' => 'plain/text']);
+        $collection = $this->getTestCollection($john, 'My Test Collection');
+        $collection->children()->attach($file1);
+
+        // List files in collection
+        $response = $this->actingAs($john)->get("api/v4/items?parent={$collection->id}");
+        $response->assertStatus(200);
+        $json = $response->json();
+
+        $list = $json['list'];
+        $this->assertSame(1, count($list));
+        $this->assertSame($file1->id, $list[0]['id']);
+
+        // List files not in a collection
+        $response = $this->actingAs($john)->get("api/v4/items?type=file");
+        $response->assertStatus(200);
+        $json = $response->json();
+
+        $list = $json['list'];
+        $this->assertSame(1, count($list));
+        $this->assertSame($file2->id, $list[0]['id']);
+
+        // Remove from collection
+        $collection->children()->detach($file1);
+
+        $response = $this->actingAs($john)->get("api/v4/items?parent={$collection->id}");
+        $response->assertStatus(200);
+        $json = $response->json();
+        $this->assertSame(0, count($response->json()['list']));
+    }
 }