diff --git a/application/controllers/GroupController.php b/application/controllers/GroupController.php
index 4dd05fdef..21fba5ebb 100644
--- a/application/controllers/GroupController.php
+++ b/application/controllers/GroupController.php
@@ -44,7 +44,7 @@ class GroupController extends AuthBackendController
             'backend',
             array(
                 'autosubmit'    => true,
-                'label'         => $this->translate('Usergroup Backend'),
+                'label'         => $this->translate('User Group Backend'),
                 'multiOptions'  => array_combine($backendNames, $backendNames),
                 'value'         => $this->params->get('backend')
             )
@@ -66,7 +66,7 @@ class GroupController extends AuthBackendController
         $this->setupLimitControl();
         $this->setupSortControl(
             array(
-                'group_name'    => $this->translate('Group'),
+                'group_name'    => $this->translate('User Group'),
                 'created_at'    => $this->translate('Created at'),
                 'last_modified' => $this->translate('Last modified')
             ),
@@ -134,7 +134,7 @@ class GroupController extends AuthBackendController
             $removeForm->addElement('button', 'btn_submit', array(
                 'escape'        => false,
                 'type'          => 'submit',
-                'class'         => 'link-like spinner',
+                'class'         => 'link-button spinner',
                 'value'         => 'btn_submit',
                 'decorators'    => array('ViewHelper'),
                 'label'         => $this->view->icon('trash'),
diff --git a/application/controllers/UserController.php b/application/controllers/UserController.php
index d080c1dae..69d4a71a5 100644
--- a/application/controllers/UserController.php
+++ b/application/controllers/UserController.php
@@ -44,7 +44,7 @@ class UserController extends AuthBackendController
             'backend',
             array(
                 'autosubmit'    => true,
-                'label'         => $this->translate('Authentication Backend'),
+                'label'         => $this->translate('User Backend'),
                 'multiOptions'  => array_combine($backendNames, $backendNames),
                 'value'         => $this->params->get('backend')
             )
@@ -140,7 +140,7 @@ class UserController extends AuthBackendController
             $removeForm->addElement('button', 'btn_submit', array(
                 'escape'        => false,
                 'type'          => 'submit',
-                'class'         => 'link-like spinner',
+                'class'         => 'link-button spinner',
                 'value'         => 'btn_submit',
                 'decorators'    => array('ViewHelper'),
                 'label'         => $this->view->icon('trash'),
diff --git a/application/views/scripts/group/list.phtml b/application/views/scripts/group/list.phtml
index 01bf3f7dd..b2bc9b920 100644
--- a/application/views/scripts/group/list.phtml
+++ b/application/views/scripts/group/list.phtml
@@ -4,30 +4,24 @@ use Icinga\Data\Extensible;
 use Icinga\Data\Reducible;
 
 if (! $this->compact): ?>
-<div class="controls">
-  <?= $this->tabs; ?>
-  <div class="grid dont-print">
-    <div class="col-1-3 text-left">
-      <?= $this->limiter ?>
+<div class="controls separated dont-print">
+    <?= $tabs; ?>
+    <div class="grid">
+        <?= $this->limiter ?>
+        <?= $this->paginator ?>
+        <?= $this->sortBox ?>
     </div>
-    <div class="col-1-3">
-      <?= $this->paginator ?>
+    <div>
+        <?= $this->backendSelection; ?>
+        <?= $this->filterEditor; ?>
     </div>
-    <div class="col-1-3 text-right">
-      <?= $this->sortBox ?>
-    </div>
-  </div>
-  <div>
-    <?= $this->backendSelection; ?>
-    <?= $this->filterEditor; ?>
-  </div>
 </div>
 <?php endif ?>
-<div class="content groups">
+<div class="content">
 <?php
 
 if (! isset($backend)) {
-    echo $this->translate('No backend found which is able to list groups') . '</div>';
+    echo $this->translate('No backend found which is able to list user groups') . '</div>';
     return;
 } else {
     $extensible = $this->hasPermission('config/authentication/groups/add') && $backend instanceof Extensible;
@@ -37,64 +31,68 @@ if (! isset($backend)) {
 
 <?php if ($extensible): ?>
     <?= $this->qlink(
-        $this->translate('Add a New User Group') ,
+        $this->translate('Add a New User Group'),
         'group/add',
         array('backend' => $backend->getName()),
         array(
             'class'             => 'button-link',
             'data-base-target'  => '_next',
-            'icon'              => 'plus',
-            'title'             => $this->translate('Create a new user group')
+            'icon'              => 'plus'
         )
     ) ?>
 <?php endif ?>
 
-<?php
-// @TODO(el): Remove $firstRow stuff
-$firstRow = true;
-foreach ($groups as $group): ?>
-  <?php if ($firstRow): ?>
-    <?php $firstRow = false; ?>
-<table data-base-target="_next" class="action-table listing-table">
-  <thead>
-    <tr>
-      <th class="group-name"><?= $this->translate('Group'); ?></th>
-     <?php if ($reducible): ?>
-      <th class="group-remove"><?= $this->translate('Remove'); ?></th>
-     <?php endif ?>
-    </tr>
-  </thead>
-  <tbody>
-  <?php endif ?>
-    <tr>
-      <td class="group-name"><?= $this->qlink($group->group_name, 'group/show', array(
-        'backend'   => $backend->getName(),
-        'group'     => $group->group_name
-      ), array(
-        'title'     => sprintf($this->translate('Show detailed information for group %s'), $group->group_name)
-      )); ?></td>
-     <?php if ($reducible): ?>
-      <td class="group-remove">
-        <?= $this->qlink(
-          null,
-          'group/remove',
-          array(
-            'backend'   => $backend->getName(),
-            'group'     => $group->group_name
-          ),
-          array(
-            'title'     => sprintf($this->translate('Remove group %s'), $group->group_name),
-            'icon'      => 'trash'
-          )
-        ); ?>
-      </td>
-     <?php endif ?>
-    </tr>
-<?php endforeach ?>
-<?php if ($groups->hasResult()): ?>
-  </tbody>
-</table>
-<?php else: ?>
-<p><?= $this->translate('No groups found matching the filter'); ?></p>
-<?php endif ?>
+<?php if (! $groups->hasResult()): ?>
+    <p><?= $this->translate('No user groups found matching the filter'); ?></p>
 </div>
+<?php endif ?>
+
+    <table data-base-target="_next" class="action-table listing-table">
+        <thead>
+            <tr>
+                <th><?= $this->translate('User Group'); ?></th>
+            <?php if ($reducible): ?>
+                <th><?= $this->translate('Remove'); ?></th>
+            <?php endif ?>
+            </tr>
+        </thead>
+        <tbody>
+        <?php foreach ($groups as $group): ?>
+            <tr>
+                <td>
+                    <?= $this->qlink(
+                        $group->group_name,
+                        'group/show',
+                        array(
+                            'backend'   => $backend->getName(),
+                            'group'     => $group->group_name
+                        ),
+                        array(
+                            'title'     => sprintf(
+                                $this->translate('Show detailed information for user group %s'),
+                                $group->group_name
+                            )
+                        )
+                    ); ?>
+                </td>
+            <?php if ($reducible): ?>
+                <td class="icon-col">
+                    <?= $this->qlink(
+                        null,
+                        'group/remove',
+                        array(
+                            'backend'   => $backend->getName(),
+                            'group'     => $group->group_name
+                        ),
+                        array(
+                            'title'     => sprintf($this->translate('Remove user group %s'), $group->group_name),
+                            'icon'      => 'trash'
+                        )
+                    ); ?>
+                </td>
+            <?php endif ?>
+            </tr>
+        <?php endforeach ?>
+        </tbody>
+    </table>
+</div>
\ No newline at end of file
diff --git a/application/views/scripts/group/show.phtml b/application/views/scripts/group/show.phtml
index f76ecdf3f..fb850a2a5 100644
--- a/application/views/scripts/group/show.phtml
+++ b/application/views/scripts/group/show.phtml
@@ -2,7 +2,6 @@
 
 use Icinga\Data\Extensible;
 use Icinga\Data\Updatable;
-use Icinga\Data\Selectable;
 
 $extensible = $this->hasPermission('config/authentication/groups/add') && $backend instanceof Extensible;
 
@@ -24,92 +23,86 @@ if ($this->hasPermission('config/authentication/groups/edit') && $backend instan
 }
 
 ?>
-<div class="controls">
- <?php if (! $this->compact): ?>
-  <?= $tabs; ?>
- <?php endif ?>
-  <h2 class="clearfix"><?= $this->escape($group->group_name) ?><span class="pull-right"><?= $editLink ?></span></h2>
-  <table class="name-value-table">
-    <tr>
-      <th><?= $this->translate('Created at'); ?></th>
-      <td><?= $group->created_at === null ? '-' : $this->formatDateTime($group->created_at); ?></td>
-    </tr>
-    <tr>
-      <th><?= $this->translate('Last modified'); ?></th>
-      <td><?= $group->last_modified === null ? '-' : $this->formatDateTime($group->last_modified); ?></td>
-    </tr>
-  </table>
-  <h2><?= $this->translate('Members'); ?></h2>
+<div class="controls separated dont-print">
 <?php if (! $this->compact): ?>
-  <?= $this->sortBox; ?>
+    <?= $tabs; ?>
 <?php endif ?>
-  <?= $this->limiter; ?>
-  <?= $this->paginator; ?>
+    <h2 class="clearfix"><?= $this->escape($group->group_name) ?><span class="pull-right"><?= $editLink ?></span></h2>
+    <table class="name-value-table">
+        <tr>
+            <th><?= $this->translate('Created at'); ?></th>
+            <td><?= $group->created_at === null ? '-' : $this->formatDateTime($group->created_at); ?></td>
+        </tr>
+        <tr>
+            <th><?= $this->translate('Last modified'); ?></th>
+            <td><?= $group->last_modified === null ? '-' : $this->formatDateTime($group->last_modified); ?></td>
+        </tr>
+    </table>
 <?php if (! $this->compact): ?>
-  <?= $this->filterEditor; ?>
+    <h2><?= $this->translate('Members'); ?></h2>
+    <div class="grid">
+        <?= $this->limiter; ?>
+        <?= $this->paginator; ?>
+        <?= $this->sortBox; ?>
+    </div>
+    <?= $this->filterEditor; ?>
 <?php endif ?>
 </div>
-<div class="content members" data-base-target="_next">
+<div class="content">
 <?php if ($extensible): ?>
     <?= $this->qlink(
-        $this->translate('Add User to Group') ,
+        $this->translate('Add New Member'),
         'group/addmember',
-        null,
         array(
-            'class'             => 'button-link',
-            'data-base-target'  => '_next',
-            'icon'              => 'plus',
-            'title'             => $this->translate('Add user to group')
+            'backend'   => $backend->getName(),
+            'group'     => $group->group_name
+        ),
+        array(
+            'icon'  => 'plus',
+            'class' => 'button-link'
         )
     ) ?>
 <?php endif ?>
 
-<?php
-
-$firstRow = true;
-foreach ($members as $member): ?>
-<?php if ($firstRow): ?>
-  <?php $firstRow = false; ?>
-  <table data-base-target="_next" class="action-table listing-table">
-    <thead>
-      <tr>
-        <th class="member-name"><?= $this->translate('Username'); ?></th>
-       <?php if (isset($removeForm)): ?>
-        <th class="member-remove"><?= $this->translate('Remove'); ?></th>
-       <?php endif ?>
-      </tr>
-    </thead>
-    <tbody>
-  <?php endif ?>
-      <tr>
-        <td class="member-name">
-        <?php if (
-          $this->hasPermission('config/authentication/users/show')
-          && method_exists($backend, 'getUserBackend')
-          && ($userBackend = $backend->getUserBackend()) !== null
-          && $userBackend instanceof Selectable
-        ): ?>
-          <?= $this->qlink($member->user_name, 'user/show', array(
-            'backend' => $userBackend->getName(),
-            'user'    => $member->user_name
-          ), array(
-            'title'   => sprintf($this->translate('Show detailed information about %s'), $member->user_name)
-          )); ?>
-        <?php else: ?>
-          <?= $this->escape($member->user_name); ?>
-        <?php endif ?>
-        </td>
-       <?php if (isset($removeForm)): ?>
-        <td class="icon-col" data-base-target="_self">
-          <?php $removeForm->getElement('user_name')->setValue($member->user_name); echo $removeForm; ?>
-        </td>
-       <?php endif ?>
-      </tr>
-<?php endforeach ?>
-<?php if ($members->hasResult()): ?>
-    </tbody>
-  </table>
-<?php else: ?>
+<?php if (! $members->hasResult()): ?>
   <p><?= $this->translate('No group member found matching the filter'); ?></p>
-<?php endif ?>
 </div>
+<?php return; endif ?>
+
+    <table data-base-target="_next" class="action-table listing-table">
+        <thead>
+            <tr>
+                <th><?= $this->translate('Username'); ?></th>
+            <?php if (isset($removeForm)): ?>
+                <th><?= $this->translate('Remove'); ?></th>
+            <?php endif ?>
+            </tr>
+        </thead>
+        <tbody>
+        <?php foreach ($members as $member): ?>
+            <tr>
+                <td>
+                <?php if (
+                    $this->hasPermission('config/authentication/users/show')
+                    && ($userBackend = $backend->getUserBackendName($member->user_name)) !== null
+                ): ?>
+                    <?= $this->qlink($member->user_name, 'user/show', array(
+                        'backend' => $userBackend,
+                        'user'    => $member->user_name
+                    ), array(
+                        'title'   => sprintf($this->translate('Show detailed information about %s'), $member->user_name)
+                    )); ?>
+                <?php else: ?>
+                    <?= $this->escape($member->user_name); ?>
+                <?php endif ?>
+                </td>
+            <?php if (isset($removeForm)): ?>
+                <td class="icon-col" data-base-target="_self">
+                    <?php $removeForm->getElement('user_name')->setValue($member->user_name); echo $removeForm; ?>
+                </td>
+            <?php endif ?>
+            </tr>
+        <?php endforeach ?>
+        </tbody>
+    </table>
+</div>
\ No newline at end of file
diff --git a/application/views/scripts/user/list.phtml b/application/views/scripts/user/list.phtml
index c89ea82e8..26114d657 100644
--- a/application/views/scripts/user/list.phtml
+++ b/application/views/scripts/user/list.phtml
@@ -1,20 +1,15 @@
 <?php
+
 use Icinga\Data\Extensible;
 use Icinga\Data\Reducible;
 
 if (! $this->compact): ?>
-<div class="controls">
-    <?= $this->tabs ?>
-    <div class="grid dont-print">
-        <div class="col-1-3 text-left">
-            <?= $this->limiter ?>
-        </div>
-        <div class="col-1-3">
-            <?= $this->paginator ?>
-        </div>
-        <div class="col-1-3 text-right">
-            <?= $this->sortBox ?>
-        </div>
+<div class="controls separated dont-print">
+    <?= $tabs ?>
+    <div class="grid">
+        <?= $this->limiter ?>
+        <?= $this->paginator ?>
+        <?= $this->sortBox ?>
     </div>
     <div>
         <?= $this->backendSelection ?>
@@ -22,20 +17,18 @@ if (! $this->compact): ?>
     </div>
 </div>
 <?php endif ?>
-
 <div class="content">
-<?php if (! isset($backend)): ?>
-    <p><?= $this->translate('No backend found which is able to list users.') ?></p>
-</div>
-<?php return; endif ?>
-<?php if (! $users->hasResult()): ?>
-    <p><?= $this->translate('No users found matching the filter.') ?></p>
-</div>
-<?php return; endif ?>
 <?php
-$extensible = $this->hasPermission('config/authentication/users/add') && $backend instanceof Extensible;
-$reducible = $this->hasPermission('config/authentication/users/remove') && $backend instanceof Reducible;
+
+if (! isset($backend)) {
+    echo $this->translate('No backend found which is able to list users') . '</div>';
+    return;
+} else {
+    $extensible = $this->hasPermission('config/authentication/users/add') && $backend instanceof Extensible;
+    $reducible = $this->hasPermission('config/authentication/users/remove') && $backend instanceof Reducible;
+}
 ?>
+
 <?php if ($extensible): ?>
     <?= $this->qlink(
         $this->translate('Add a New User') ,
@@ -44,12 +37,17 @@ $reducible = $this->hasPermission('config/authentication/users/remove') && $back
         array(
             'class'             => 'button-link',
             'data-base-target'  => '_next',
-            'icon'              => 'plus',
-            'title'             => $this->translate('Create a new user')
+            'icon'              => 'plus'
         )
     ) ?>
 <?php endif ?>
-    <table class="action-table listing-table" data-base-target="_next">
+
+<?php if (! $users->hasResult()): ?>
+    <p><?= $this->translate('No users found matching the filter') ?></p>
+</div>
+<?php return; endif ?>
+
+    <table data-base-target="_next" class="action-table listing-table">
     <thead>
         <tr>
             <th><?= $this->translate('Username') ?></th>
@@ -91,4 +89,4 @@ $reducible = $this->hasPermission('config/authentication/users/remove') && $back
     <?php endforeach ?>
     </tbody>
     </table>
-</div>
+</div>
\ No newline at end of file
diff --git a/application/views/scripts/user/show.phtml b/application/views/scripts/user/show.phtml
index ee3aa6809..2fbdab551 100644
--- a/application/views/scripts/user/show.phtml
+++ b/application/views/scripts/user/show.phtml
@@ -22,93 +22,90 @@ if ($this->hasPermission('config/authentication/users/edit') && $backend instanc
 }
 
 ?>
-<div class="controls">
+<div class="controls separated dont-print">
 <?php if (! $this->compact): ?>
-  <?= $tabs; ?>
+    <?= $tabs; ?>
 <?php endif ?>
-  <h2 class="clearfix"><?= $this->escape($user->user_name) ?><span class="pull-right"><?= $editLink ?></span></h2>
-  <table class="name-value-table">
-    <tr>
-      <th><?= $this->translate('State'); ?></th>
-      <td><?= $user->is_active === null ? '-' : ($user->is_active ? $this->translate('Active') : $this->translate('Inactive')); ?></td>
-    </tr>
-    <tr>
-      <th><?= $this->translate('Created at'); ?></th>
-      <td><?= $user->created_at === null ? '-' : $this->formatDateTime($user->created_at); ?></td>
-    </tr>
-    <tr>
-      <th><?= $this->translate('Last modified'); ?></th>
-      <td><?= $user->last_modified === null ? '-' : $this->formatDateTime($user->last_modified); ?></td>
-    </tr>
-  </table>
-  <h2><?= $this->translate('Group Memberships'); ?></h2>
+    <h2 class="clearfix"><?= $this->escape($user->user_name) ?><span class="pull-right"><?= $editLink ?></span></h2>
+    <table class="name-value-table">
+        <tr>
+            <th><?= $this->translate('State'); ?></th>
+            <td><?= $user->is_active === null ? '-' : ($user->is_active ? $this->translate('Active') : $this->translate('Inactive')); ?></td>
+        </tr>
+        <tr>
+            <th><?= $this->translate('Created at'); ?></th>
+            <td><?= $user->created_at === null ? '-' : $this->formatDateTime($user->created_at); ?></td>
+        </tr>
+        <tr>
+            <th><?= $this->translate('Last modified'); ?></th>
+            <td><?= $user->last_modified === null ? '-' : $this->formatDateTime($user->last_modified); ?></td>
+        </tr>
+    </table>
 <?php if (! $this->compact): ?>
-  <?= $this->sortBox; ?>
-<?php endif ?>
-  <?= $this->limiter; ?>
-  <?= $this->paginator; ?>
-<?php if (! $this->compact): ?>
-  <?= $this->filterEditor; ?>
+    <h2><?= $this->translate('Group Memberships'); ?></h2>
+    <div class="grid">
+        <?= $this->limiter; ?>
+        <?= $this->paginator; ?>
+        <?= $this->sortBox; ?>
+    </div>
+    <?= $this->filterEditor; ?>
 <?php endif ?>
 </div>
-<div class="content memberships">
-    <?php if ($showCreateMembershipLink): ?>
+<div class="content">
+<?php if ($showCreateMembershipLink): ?>
     <?= $this->qlink(
-        $this->translate('Add User to Group') ,
+        $this->translate('Create New Membership'),
         'user/createmembership',
-        array('backend' => $backend->getName()),
         array(
-            'class'             => 'button-link',
-            'data-base-target'  => '_next',
-            'icon'              => 'plus',
-            'title'             => $this->translate('Add user to user group')
+            'backend'   => $backend->getName(),
+            'user'      => $user->user_name
+        ),
+        array(
+            'icon'  => 'plus',
+            'class' => 'button-link'
         )
     ) ?>
-    <?php endif ?>
-<?php
-// @TODO(el): Remove that $firstRow thingy
-$firstRow = true;
-foreach ($memberships as $membership): ?>
-<?php if ($firstRow): ?>
-  <?php $firstRow = false; ?>
-  <table data-base-target="_next" class="action-table listing-table">
-    <thead>
-      <tr>
-        <th class="membership-group"><?= $this->translate('Group'); ?></th>
-        <th class="membership-cancel"><?= $this->translate('Cancel', 'group.membership'); ?></th>
-      </tr>
-    </thead>
-    <tbody>
-<?php endif ?>
-      <tr>
-        <td class="membership-group">
-         <?php if ($this->hasPermission('config/authentication/groups/show') && $membership->backend instanceof Selectable): ?>
-          <?= $this->qlink($membership->group_name, 'group/show', array(
-            'backend' => $membership->backend->getName(),
-            'group'   => $membership->group_name
-          ), array(
-            'title'   => sprintf($this->translate('Show detailed information for group %s'), $membership->group_name)
-          )); ?>
-         <?php else: ?>
-          <?= $this->escape($membership->group_name); ?>
-         <?php endif ?>
-        </td>
-        <td class="membership-cancel" data-base-target="_self">
-       <?php if (isset($removeForm) && $membership->backend instanceof Reducible): ?>
-          <?= $removeForm->setAction($this->url('group/removemember', array(
-            'backend'   => $membership->backend->getName(),
-            'group'     => $membership->group_name
-          ))); ?>
-       <?php else: ?>
-          -
-       <?php endif ?>
-        </td>
-      </tr>
-<?php endforeach ?>
-<?php if ($memberships->hasResult()): ?>
-    </tbody>
-  </table>
-<?php else: ?>
-  <p><?= $this->translate('No memberships found matching the filter'); ?></p>
 <?php endif ?>
+
+<?php if (! $memberships->hasResult()): ?>
+    <p><?= $this->translate('No memberships found matching the filter'); ?></p>
 </div>
+<?php return; endif ?>
+
+    <table data-base-target="_next" class="action-table listing-table">
+        <thead>
+            <tr>
+                <th><?= $this->translate('Group'); ?></th>
+                <th><?= $this->translate('Cancel', 'group.membership'); ?></th>
+            </tr>
+        </thead>
+        <tbody>
+        <?php foreach ($memberships as $membership): ?>
+            <tr>
+                <td>
+                <?php if ($this->hasPermission('config/authentication/groups/show') && $membership->backend instanceof Selectable): ?>
+                    <?= $this->qlink($membership->group_name, 'group/show', array(
+                        'backend' => $membership->backend->getName(),
+                        'group'   => $membership->group_name
+                    ), array(
+                        'title'   => sprintf($this->translate('Show detailed information for group %s'), $membership->group_name)
+                    )); ?>
+                <?php else: ?>
+                    <?= $this->escape($membership->group_name); ?>
+                <?php endif ?>
+                </td>
+                <td class="icon-col" data-base-target="_self">
+                <?php if (isset($removeForm) && $membership->backend instanceof Reducible): ?>
+                    <?= $removeForm->setAction($this->url('group/removemember', array(
+                        'backend'   => $membership->backend->getName(),
+                        'group'     => $membership->group_name
+                    ))); ?>
+                <?php else: ?>
+                    -
+                <?php endif ?>
+                </td>
+            </tr>
+        <?php endforeach ?>
+        </tbody>
+    </table>
+</div>
\ No newline at end of file
diff --git a/library/Icinga/Authentication/User/DbUserBackend.php b/library/Icinga/Authentication/User/DbUserBackend.php
index c0c949fd7..e004a56c0 100644
--- a/library/Icinga/Authentication/User/DbUserBackend.php
+++ b/library/Icinga/Authentication/User/DbUserBackend.php
@@ -130,6 +130,7 @@ class DbUserBackend extends DbRepository implements UserBackendInterface, Inspec
      */
     public function insert($table, array $bind)
     {
+        $this->requireTable($table);
         $bind['created_at'] = date('Y-m-d H:i:s');
         $this->ds->insert(
             $this->prependTablePrefix($table),
@@ -150,6 +151,7 @@ class DbUserBackend extends DbRepository implements UserBackendInterface, Inspec
      */
     public function update($table, array $bind, Filter $filter = null)
     {
+        $this->requireTable($table);
         $bind['last_modified'] = date('Y-m-d H:i:s');
         if ($filter) {
             $filter = $this->requireFilter($table, $filter);
diff --git a/library/Icinga/Authentication/User/LdapUserBackend.php b/library/Icinga/Authentication/User/LdapUserBackend.php
index f3a852115..b5bd51f45 100644
--- a/library/Icinga/Authentication/User/LdapUserBackend.php
+++ b/library/Icinga/Authentication/User/LdapUserBackend.php
@@ -341,6 +341,27 @@ class LdapUserBackend extends LdapRepository implements UserBackendInterface, In
         return $table;
     }
 
+    /**
+     * Validate that the given column is a valid query target and return it or the actual name if it's an alias
+     *
+     * @param   string              $table  The table where to look for the column or alias
+     * @param   string              $name   The name or alias of the column to validate
+     * @param   RepositoryQuery     $query  An optional query to pass as context
+     *
+     * @return  string                      The given column's name
+     *
+     * @throws  QueryException              In case the given column is not a valid query column
+     */
+    public function requireQueryColumn($table, $name, RepositoryQuery $query = null)
+    {
+        $column = parent::requireQueryColumn($table, $name, $query);
+        if ($name === 'user_name' && $query !== null) {
+            $query->getQuery()->setUnfoldAttribute('user_name');
+        }
+
+        return $column;
+    }
+
     /**
      * Authenticate the given user
      *
diff --git a/library/Icinga/Authentication/UserGroup/DbUserGroupBackend.php b/library/Icinga/Authentication/UserGroup/DbUserGroupBackend.php
index a114cc8d1..6f5c2e9dd 100644
--- a/library/Icinga/Authentication/UserGroup/DbUserGroupBackend.php
+++ b/library/Icinga/Authentication/UserGroup/DbUserGroupBackend.php
@@ -217,6 +217,18 @@ class DbUserGroupBackend extends DbRepository implements UserGroupBackendInterfa
         return $memberships;
     }
 
+    /**
+     * Return the name of the backend that is providing the given user
+     *
+     * @param   string  $username   Currently unused
+     *
+     * @return  null|string     The name of the backend or null in case this information is not available
+     */
+    public function getUserBackendName($username)
+    {
+        return null; // TODO(10373): Store this to the database when inserting and fetch it here
+    }
+
     /**
      * Join group into group_membership
      *
@@ -238,7 +250,7 @@ class DbUserGroupBackend extends DbRepository implements UserGroupBackendInterfa
      */
     protected function joinGroupMembership(RepositoryQuery $query)
     {
-        $query->getQuery()->join(
+        $query->getQuery()->joinLeft(
             $this->requireTable('group_membership'),
             'g.id = gm.group_id',
             array()
diff --git a/library/Icinga/Authentication/UserGroup/LdapUserGroupBackend.php b/library/Icinga/Authentication/UserGroup/LdapUserGroupBackend.php
index 2aa615a84..9a4ab53c0 100644
--- a/library/Icinga/Authentication/UserGroup/LdapUserGroupBackend.php
+++ b/library/Icinga/Authentication/UserGroup/LdapUserGroupBackend.php
@@ -5,6 +5,7 @@ namespace Icinga\Authentication\UserGroup;
 
 use Icinga\Authentication\User\UserBackend;
 use Icinga\Authentication\User\LdapUserBackend;
+use Icinga\Application\Logger;
 use Icinga\Data\ConfigObject;
 use Icinga\Exception\ConfigurationError;
 use Icinga\Exception\ProgrammingError;
@@ -454,12 +455,48 @@ class LdapUserGroupBackend extends LdapRepository implements UserGroupBackendInt
             )
         );
         if (! $this->isAmbiguous($this->groupClass, $this->groupMemberAttribute)) {
+            $rules['group_membership']['user_name'] = 'user_name';
+            $rules['group_membership']['user'] = 'user_name';
             $rules['group']['user_name'] = 'user_name';
+            $rules['group']['user'] = 'user_name';
         }
 
         return $rules;
     }
 
+    /**
+     * Return the distinguished name for the given uid or gid
+     *
+     * @param   string  $name
+     *
+     * @return  string
+     */
+    protected function persistUserName($name)
+    {
+        $userDn = $this->ds
+            ->select()
+            ->from($this->userClass, array())
+            ->where($this->userNameAttribute, $name)
+            ->setUsePagedResults(false)
+            ->fetchDn();
+        if ($userDn) {
+            return $userDn;
+        }
+
+        $groupDn = $this->ds
+            ->select()
+            ->from($this->groupClass, array())
+            ->where($this->groupNameAttribute, $name)
+            ->setUsePagedResults(false)
+            ->fetchDn();
+        if ($groupDn) {
+            return $groupDn;
+        }
+
+        Logger::debug('Unable to persist uid or gid "%s" in repository "%s". No DN found.', $name, $this->getName());
+        return $name;
+    }
+
     /**
      * Return the uid for the given distinguished name
      *
@@ -564,6 +601,21 @@ class LdapUserGroupBackend extends LdapRepository implements UserGroupBackendInt
         return $groups;
     }
 
+    /**
+     * Return the name of the backend that is providing the given user
+     *
+     * @param   string  $username   Unused
+     *
+     * @return  null|string     The name of the backend or null in case this information is not available
+     */
+    public function getUserBackendName($username)
+    {
+        $userBackend = $this->getUserBackend();
+        if ($userBackend !== null) {
+            return $userBackend->getName();
+        }
+    }
+
     /**
      * Apply the given configuration on this backend
      *
diff --git a/library/Icinga/Authentication/UserGroup/UserGroupBackendInterface.php b/library/Icinga/Authentication/UserGroup/UserGroupBackendInterface.php
index a567d1f0a..31dd2c50d 100644
--- a/library/Icinga/Authentication/UserGroup/UserGroupBackendInterface.php
+++ b/library/Icinga/Authentication/UserGroup/UserGroupBackendInterface.php
@@ -34,4 +34,13 @@ interface UserGroupBackendInterface
      * @return  array
      */
     public function getMemberships(User $user);
+
+    /**
+     * Return the name of the backend that is providing the given user
+     *
+     * @param   string  $username
+     *
+     * @return  null|string     The name of the backend or null in case this information is not available
+     */
+    public function getUserBackendName($username);
 }
diff --git a/library/Icinga/Repository/DbRepository.php b/library/Icinga/Repository/DbRepository.php
index 89701cb9d..27144d097 100644
--- a/library/Icinga/Repository/DbRepository.php
+++ b/library/Icinga/Repository/DbRepository.php
@@ -297,6 +297,7 @@ abstract class DbRepository extends Repository implements Extensible, Updatable,
      */
     public function insert($table, array $bind)
     {
+        $this->requireTable($table);
         $this->ds->insert($this->prependTablePrefix($table), $this->requireStatementColumns($table, $bind));
     }
 
@@ -309,6 +310,8 @@ abstract class DbRepository extends Repository implements Extensible, Updatable,
      */
     public function update($table, array $bind, Filter $filter = null)
     {
+        $this->requireTable($table);
+
         if ($filter) {
             $filter = $this->requireFilter($table, $filter);
         }
@@ -324,6 +327,8 @@ abstract class DbRepository extends Repository implements Extensible, Updatable,
      */
     public function delete($table, Filter $filter = null)
     {
+        $this->requireTable($table);
+
         if ($filter) {
             $filter = $this->requireFilter($table, $filter);
         }
diff --git a/public/css/icinga/main-content.less b/public/css/icinga/main-content.less
index 54430ef60..624b21eec 100644
--- a/public/css/icinga/main-content.less
+++ b/public/css/icinga/main-content.less
@@ -233,83 +233,6 @@ div.content.users {
   }
 }
 
-div.content.memberships {
-  table.membership-list {
-    th.membership-cancel {
-      width: 8em;
-      padding-right: 0.5em;
-      text-align: right;
-    }
-
-    td.membership-cancel {
-      text-align: right;
-
-      form button.link-like {
-        color: inherit;
-      }
-    }
-  }
-
-  p {
-    margin-top: 0;
-  }
-
-  a.membership-create {
-    display: block;
-    margin-top: 1em;
-  }
-}
-
-div.content.groups {
-  table.group-list {
-    th.group-remove {
-      width: 8em;
-      padding-right: 0.5em;
-      text-align: right;
-    }
-
-    td.group-remove {
-      text-align: right;
-    }
-  }
-
-  p {
-    margin-top: 0;
-  }
-
-  a.group-add {
-    display: block;
-    margin-top: 1em;
-  }
-}
-
-div.content.members {
-  table.member-list {
-    th.member-remove {
-      width: 8em;
-      padding-right: 0.5em;
-      text-align: right;
-    }
-
-    td.member-remove {
-      text-align: right;
-
-      form button.link-like {
-        color: inherit;
-      }
-    }
-  }
-
-  p {
-    margin-top: 0;
-  }
-
-  a.member-add {
-    display: block;
-    margin-top: 1em;
-  }
-}
-
 form.backend-selection {
   float: right;