diff --git a/openslides/agenda/models.py b/openslides/agenda/models.py
index e407f9193..f65d595e1 100644
--- a/openslides/agenda/models.py
+++ b/openslides/agenda/models.py
@@ -5,7 +5,7 @@ from django.contrib.auth.models import AnonymousUser
 from django.contrib.contenttypes.fields import GenericForeignKey
 from django.contrib.contenttypes.models import ContentType
 from django.core.exceptions import ValidationError
-from django.db import models
+from django.db import models, transaction
 from django.utils.translation import ugettext as _
 from django.utils.translation import ugettext_lazy, ugettext_noop
 
@@ -52,6 +52,7 @@ class ItemManager(models.Manager):
 
         yield from get_children(filter(lambda item: item.parent is None, item_queryset))
 
+    @transaction.atomic
     def set_tree(self, tree):
         """
         Sets the agenda tree.
@@ -71,15 +72,25 @@ class ItemManager(models.Manager):
                 yield from walk_items(element.get('children', []), element['id'])
 
         touched_items = set()
-        for item_pk, parent_pk, weight in walk_items(tree):
+        db_items = dict((item.pk, item) for item in Item.objects.all())
+        for item_id, parent_id, weight in walk_items(tree):
             # Check that the item is only once in the tree to prevent invalid trees
-            if item_pk in touched_items:
-                raise ValueError("Item %d is more then once in the tree" % item_pk)
-            touched_items.add(item_pk)
+            if item_id in touched_items:
+                raise ValueError("Item {} is more then once in the tree.".format(item_id))
+            touched_items.add(item_id)
 
-            Item.objects.filter(pk=item_pk).update(
-                parent_id=parent_pk,
-                weight=weight)
+            try:
+                db_item = db_items[item_id]
+            except KeyError:
+                raise ValueError("Item {} is not in the database.".format(item_id))
+
+            # Check if the item has changed and update it
+            # Note: Do not use Item.objects.update, so that the items are sent
+            #       to the clients via autoupdate
+            if db_item.parent_id != parent_id or db_item.weight != weight:
+                db_item.parent_id = parent_id
+                db_item.weight = weight
+                db_item.save()
 
 
 class Item(RESTModelMixin, models.Model):
diff --git a/openslides/agenda/serializers.py b/openslides/agenda/serializers.py
index 611a10520..919be9416 100644
--- a/openslides/agenda/serializers.py
+++ b/openslides/agenda/serializers.py
@@ -68,4 +68,6 @@ class ItemSerializer(ModelSerializer):
             'speakers',
             'speaker_list_closed',
             'content_object',
-            'tags',)
+            'tags',
+            'weight',
+            'parent',)
diff --git a/openslides/agenda/static/js/agenda/agenda.js b/openslides/agenda/static/js/agenda/agenda.js
index 7934cbd80..e9b33b1bb 100644
--- a/openslides/agenda/static/js/agenda/agenda.js
+++ b/openslides/agenda/static/js/agenda/agenda.js
@@ -75,9 +75,6 @@ angular.module('OpenSlidesApp.agenda.site', ['OpenSlidesApp.agenda'])
             resolve: {
                 items: function(Agenda) {
                     return Agenda.findAll();
-                },
-                tree: function($http) {
-                    return $http.get('/rest/agenda/item/tree/');
                 }
             }
         })
@@ -120,9 +117,6 @@ angular.module('OpenSlidesApp.agenda.site', ['OpenSlidesApp.agenda'])
             resolve: {
                 items: function(Agenda) {
                     return Agenda.findAll();
-                },
-                tree: function($http) {
-                    return $http.get('/rest/agenda/item/tree/');
                 }
             },
             url: '/sort',
@@ -134,30 +128,75 @@ angular.module('OpenSlidesApp.agenda.site', ['OpenSlidesApp.agenda'])
         });
 })
 
-.controller('ItemListCtrl', function($scope, $http, Agenda, tree, Projector) {
-    Agenda.bindAll({}, $scope, 'items');
+.factory('AgendaTree', [
+    function () {
+        return {
+            getTree: function (items) {
+                // sortieren nach weight???
 
-    // get a 'flat' (ordered) array of agenda tree to display in table
-    $scope.flattenedTree = buildTree(tree.data);
-    function buildTree(tree, level) {
-        var level = level || 0
-        var nodes = [];
-        var defaultlevel = level;
-        _.each(tree, function(node) {
-            level = defaultlevel;
-            if (node.id) {
-                nodes.push({ id: node.id, level: level });
-            }
-            if (node.children) {
-                level++;
-                var child = buildTree(node.children, level);
-                if (child.length) {
-                    nodes = nodes.concat(child);
+                // Build a dict with all children (dict-value) to a specific
+                // item id (dict-key).
+                var itemChildren = {};
+
+                _.each(items, function (item) {
+                    if (item.parent_id) {
+                        // Add item to his parent. If it is the first child, then
+                        // create a new list.
+                        try {
+                            itemChildren[item.parent_id].push(item);
+                        } catch (error) {
+                            itemChildren[item.parent_id] = [item];
+                        }
+                    }
+
+                });
+
+                // Recursive function that generates a nested list with all
+                // items with there children
+                function getChildren(items) {
+                    var returnItems = [];
+                    _.each(items, function (item) {
+                        returnItems.push({
+                            item: item,
+                            children: getChildren(itemChildren[item.id]),
+                            id: item.id,
+                        });
+                    });
+                    return returnItems;
                 }
-            }
-        });
-        return nodes;
+
+                // Generates the list of root items (with no parents)
+                var parentItems = items.filter(function (item) {
+                    return !item.parent_id;
+                });
+                return getChildren(parentItems);
+            },
+            // Returns a list of all items as a flat tree the attribute parentCount
+            getFlatTree: function(items) {
+                var tree = this.getTree(items);
+                var flatItems = [];
+
+                function generateFatTree(tree, parentCount) {
+                    _.each(tree, function (item) {
+                        item.item.parentCount = parentCount;
+                        flatItems.push(item.item);
+                        generateFatTree(item.children, parentCount + 1);
+                    });
+                }
+                generateFatTree(tree, 0);
+                return flatItems;
+            },
+        }
     }
+])
+
+.controller('ItemListCtrl', function($scope, $http, Agenda, Projector, AgendaTree) {
+    // Bind agenda tree to the scope
+    $scope.$watch(function () {
+        return Agenda.lastModified();
+    }, function () {
+        $scope.items = AgendaTree.getFlatTree(Agenda.getAll());
+    });
 
     // save changed item
     $scope.save = function (item) {
@@ -269,16 +308,20 @@ angular.module('OpenSlidesApp.agenda.site', ['OpenSlidesApp.agenda'])
     };
 })
 
-.controller('AgendaSortCtrl', function($scope, $http, Agenda, tree) {
-    Agenda.bindAll({}, $scope, 'items');
-    $scope.tree = tree.data;
+.controller('AgendaSortCtrl', function($scope, $http, Agenda, AgendaTree) {
+    // Bind agenda tree to the scope
+    $scope.$watch(function () {
+        return Agenda.lastModified();
+    }, function () {
+        $scope.items = AgendaTree.getTree(Agenda.getAll());
+    });
 
     // set changed agenda tree
     $scope.treeOptions = {
-        dropped: function(e) {
-            $http.put('/rest/agenda/item/tree/', {tree: $scope.tree});
+        dropped: function() {
+            $http.put('/rest/agenda/item/tree/', {tree: $scope.items});
         }
-      };
+    };
 })
 
 .controller('AgendaImportCtrl', function($scope, $state, Agenda) {
diff --git a/openslides/agenda/static/templates/agenda/item-list.html b/openslides/agenda/static/templates/agenda/item-list.html
index 9eda8b96c..0fbc07f9d 100644
--- a/openslides/agenda/static/templates/agenda/item-list.html
+++ b/openslides/agenda/static/templates/agenda/item-list.html
@@ -52,42 +52,44 @@
       <th os-perms="agenda.can_manage core.can_manage_projector" class="minimum">
         <translate>Actions</translate>
   <tbody>
-    <tr ng-repeat="node in flattenedTree | filter: filter.search"
-        ng-class="{ 'activeline': (items | filter: {id: node.id})[0].isProjected() }">
-      <td><input type="checkbox" ng-model="(items | filter: {id: node.id})[0].closed" ng-click="save(node.id)">
+    <tr ng-repeat="item in items"
+        ng-class="{ 'activeline': item.isProjected() }">
       <td>
-        <span ng-repeat="n in [].constructor(node.level) track by $index">&ndash;</span>
-        <a ui-sref="agenda.item.detail({id: node.id})">
-          {{ (items | filter: {id: node.id})[0].item_number }}
-          {{ (items | filter: {id: node.id})[0].title }}
+        <!-- Please do not use ng-click, but ng-change -->
+        <input type="checkbox" ng-model="item.closed" ng-click="save(item.id)">
+      <td>
+        <span ng-repeat="n in [].constructor(item.parentCount) track by $index">&ndash;</span>
+        <a ui-sref="agenda.item.detail({id: item.id})">
+          {{ item.item_number }}
+          {{ item.title }}
         </a>
-        <div ng-if="(items | filter: {id: node.id})[0].comment">
-          <small><i class="fa fa-info-circle"></i> {{ (items | filter: {id: node.id})[0].comment }}</small>
+        <div ng-if="item.comment">
+          <small><i class="fa fa-info-circle"></i> {{ item.comment }}</small>
         </div>
       <td os-perms="agenda.can_manage" class="optional">
-        <a href="#" editable-number="(items | filter: {id: node.id})[0].duration" e-min="1" onaftersave="save(node.id)">
-          {{ (items | filter: {id: node.id})[0].duration }}
+        <a href="#" editable-number="item.duration" e-min="1" onaftersave="save(item.id)">
+          {{ item.duration }}
         </a>
-        <span ng-if="(items | filter: {id: node.id})[0].duration" translate>min</span>
+        <span ng-if="item.duration" translate>min</span>
       <td os-perms="agenda.can_manage core.can_manage_projector" class="nobr">
         <!-- project -->
         <a os-perms="core.can_manage_projector" class="btn btn-default btn-sm"
-            ng-class="{ 'btn-primary': (items | filter: {id: node.id})[0].isProjected() }"
-            ng-click="(items | filter: {id: node.id})[0].project()"
+            ng-class="{ 'btn-primary': item.isProjected() }"
+            ng-click="item.project()"
             title="{{ 'Project item' | translate }}">
           <i class="fa fa-video-camera"></i>
         </a>
         <!-- edit -->
-        <a ui-sref="agenda.item.detail.update({id: node.id })" os-perms="agenda.can_manage"
+        <a ui-sref="agenda.item.detail.update({id: item.id })" os-perms="agenda.can_manage"
             class="btn btn-default btn-sm"
-            title="{{ 'Edit' | translate}}">
+            title="{{ 'Edit' | translate }}">
           <i class="fa fa-pencil"></i>
         </a>
         <!-- delete -->
         <a os-perms="agenda.can_manage" class="btn btn-danger btn-sm"
             ng-bootbox-confirm="Are you sure you want to delete
-              <b>{{ (items | filter: {id: node.id})[0].title }}</b>?"
-            ng-bootbox-confirm-action="delete(node.id)"
+              <b>{{ item.title }}</b>?"
+            ng-bootbox-confirm-action="delete(item.id)"
             title="{{ 'Delete' | translate }}">
           <i class="fa fa-trash-o"></i>
         </a>
diff --git a/openslides/agenda/static/templates/agenda/item-sort.html b/openslides/agenda/static/templates/agenda/item-sort.html
index 934c047d4..aec04f62d 100644
--- a/openslides/agenda/static/templates/agenda/item-sort.html
+++ b/openslides/agenda/static/templates/agenda/item-sort.html
@@ -9,19 +9,21 @@
 
 <p translate>Drag and drop items to change the order of the agenda. Your modification will be saved directly.</p>
 
+<div ui-tree callbacks="treeOptions">
+  <ol ui-tree-nodes="" ng-model="items" id="tree-root">
+    <li ng-repeat="item in items" ui-tree-node ng-include="'nodes_renderer.html'">
+  </ol>
+</div>
+
+
 <!-- Nested node template -->
 <script type="text/ng-template" id="nodes_renderer.html">
   <div ui-tree-handle>
-    {{ (items | filter: {id: node.id})[0].item_number }}
-    {{ (items | filter: {id: node.id})[0].title }}
+    {{ item.item.item_number }}
+    {{ item.item.title }}
   </div>
-  <ol ui-tree-nodes="" ng-model="node.children">
-    <li ng-repeat="node in node.children" ui-tree-node ng-include="'nodes_renderer.html'">
+  <ol ui-tree-nodes="" ng-model="item.children">
+    <li ng-repeat="item in item.children" ui-tree-node ng-include="'nodes_renderer.html'">
   </ol>
 </script>
 
-<div ui-tree callbacks="treeOptions">
-  <ol ui-tree-nodes="" ng-model="tree" id="tree-root">
-    <li ng-repeat="node in tree" ui-tree-node ng-include="'nodes_renderer.html'">
-  </ol>
-</div>
diff --git a/tests/integration/agenda/test_views.py b/tests/integration/agenda/test_views.py
index 4120136dc..122b64cbc 100644
--- a/tests/integration/agenda/test_views.py
+++ b/tests/integration/agenda/test_views.py
@@ -58,7 +58,7 @@ class AgendaTreeTest(TestCase):
         response = self.client.put('/rest/agenda/item/tree/', {'tree': tree}, format='json')
 
         self.assertEqual(response.status_code, 400)
-        self.assertEqual(response.data, {'detail': "Item 1 is more then once in the tree"})
+        self.assertEqual(response.data, {'detail': "Item 1 is more then once in the tree."})
 
     def test_tree_with_empty_children(self):
         """
@@ -72,13 +72,14 @@ class AgendaTreeTest(TestCase):
 
     def test_tree_with_unknown_item(self):
         """
-        Tests that unknown items are ignored.
+        Tests that unknown items lead to an error.
         """
         tree = [{'id': 500}]
 
         response = self.client.put('/rest/agenda/item/tree/', {'tree': tree}, format='json')
 
-        self.assertEqual(response.status_code, 200)
+        self.assertEqual(response.status_code, 400)
+        self.assertEqual(response.data, {'detail': "Item 500 is not in the database."})
 
 
 class TestAgendaPDF(TestCase):