diff --git a/mayan/apps/tags/api_views.py b/mayan/apps/tags/api_views.py
index ea6ee64631..3243970280 100644
--- a/mayan/apps/tags/api_views.py
+++ b/mayan/apps/tags/api_views.py
@@ -14,7 +14,8 @@ from rest_api.filters import MayanObjectPermissionsFilter
 from rest_api.permissions import MayanPermission
 
 from .models import Tag
-from .permissions import PERMISSION_TAG_REMOVE, PERMISSION_TAG_VIEW
+from .permissions import (PERMISSION_TAG_ATTACH, PERMISSION_TAG_REMOVE,
+                          PERMISSION_TAG_VIEW)
 from .serializers import TagSerializer
 
 
@@ -105,9 +106,34 @@ class APIDocumentTagRemoveView(generics.DestroyAPIView):
         tag = self.get_object()
         document = self.get_document()
 
-        document.tags.remove(tag)
+        tag.documents.remove(document)
         return Response(status=status.HTTP_204_NO_CONTENT)
 
     def get_queryset(self):
         document = self.get_document()
         return document.tags.all()
+
+
+class APIDocumentTagAddView(generics.CreateAPIView):
+    """
+    Attach a tag to a document.
+    """
+
+    queryset = Tag.objects.all()
+    serializer_class = TagSerializer
+
+    def get_document(self):
+        document = get_object_or_404(Document, pk=self.kwargs['document_pk'])
+        try:
+            Permission.objects.check_permissions(self.request.user, [PERMISSION_TAG_ATTACH])
+        except PermissionDenied:
+            AccessEntry.objects.check_access(PERMISSION_TAG_ATTACH, self.request.user, document)
+
+        return document
+
+    def post(self, request, *args, **kwargs):
+        tag = self.get_object()
+        document = self.get_document()
+
+        tag.documents.add(document)
+        return Response(status=status.HTTP_201_CREATED)
diff --git a/mayan/apps/tags/urls.py b/mayan/apps/tags/urls.py
index 66a265ed06..fc2749d358 100644
--- a/mayan/apps/tags/urls.py
+++ b/mayan/apps/tags/urls.py
@@ -2,8 +2,9 @@ from __future__ import absolute_import
 
 from django.conf.urls import patterns, url
 
-from .api_views import (APIDocumentTagRemoveView, APIDocumentTagListView,
-                        APITagDocumentListView, APITagListView, APITagView)
+from .api_views import (APIDocumentTagAddView, APIDocumentTagRemoveView,
+                        APIDocumentTagListView, APITagDocumentListView,
+                        APITagListView, APITagView)
 from .views import TagTaggedItemListView
 
 urlpatterns = patterns('tags.views',
@@ -31,4 +32,5 @@ api_urls = patterns('',
     url(r'^tags/$', APITagListView.as_view(), name='tag-list'),
     url(r'^document/(?P<pk>[0-9]+)/tags/$', APIDocumentTagListView.as_view(), name='document-tag-list'),
     url(r'^document/(?P<document_pk>[0-9]+)/tags/(?P<pk>[0-9]+)/remove/$', APIDocumentTagRemoveView.as_view(), name='document-tag-remove'),
+    url(r'^document/(?P<document_pk>[0-9]+)/tags/(?P<pk>[0-9]+)/add/$', APIDocumentTagAddView.as_view(), name='document-tag-add'),
 )