diff --git a/application/controllers/ConfigController.php b/application/controllers/ConfigController.php
index 7ee73a0d..f55f9294 100644
--- a/application/controllers/ConfigController.php
+++ b/application/controllers/ConfigController.php
@@ -2,6 +2,7 @@
 
 namespace Icinga\Module\Director\Controllers;
 
+use Icinga\Module\Director\ConfigDiff;
 use Icinga\Module\Director\IcingaConfig\IcingaConfig;
 use Icinga\Module\Director\Util;
 use Icinga\Module\Director\Web\Controller\ActionController;
@@ -173,6 +174,56 @@ class ConfigController extends ActionController
         );
     }
 
+    public function diffAction()
+    {
+        $db = $this->db();
+        $this->view->title = $this->translate('Config diff');
+
+        $tabs = $this->getTabs()->add('diff', array(
+            'label'     => $this->translate('Config diff'),
+            'url'       => $this->getRequest()->getUrl()
+        ))->activate('diff');
+
+        $leftSum  = $this->view->leftSum  = $this->params->get('left');
+        $rightSum = $this->view->rightSum = $this->params->get('right');
+        $left  = IcingaConfig::load(Util::hex2binary($leftSum), $db);
+
+        $this->view->configs = $db->enumDeployedConfigs();
+        if ($rightSum === null) {
+            return;
+        }
+
+        $right = IcingaConfig::load(Util::hex2binary($rightSum), $db);
+        $this->view->table = $this
+            ->loadTable('ConfigFileDiff')
+            ->setConnection($this->db())
+            ->setLeftChecksum($leftSum)
+            ->setRightChecksum($rightSum);
+    }
+
+    public function filediffAction()
+    {
+        $db = $this->db();
+        $leftSum  = $this->params->get('left');
+        $rightSum = $this->params->get('right');
+        $filename = $this->view->filename = $this->params->get('file_path');
+
+        $left = IcingaConfig::load(Util::hex2binary($leftSum), $db);
+        $right = IcingaConfig::load(Util::hex2binary($rightSum), $db);
+
+        $leftFile  = $left->getFile($filename);
+        $rightFile = $right->getFile($filename);
+
+        $d = ConfigDiff::create($leftFile, $rightFile);
+
+        $this->view->title = sprintf(
+            $this->translate('Config file "%s"'),
+            $filename
+        );
+
+        $this->view->output = $d->renderHtml();
+    }
+
     protected function overviewTabs()
     {
         $this->view->tabs = $this->getTabs()->add(
diff --git a/application/tables/ConfigFileDiffTable.php b/application/tables/ConfigFileDiffTable.php
new file mode 100644
index 00000000..347c9967
--- /dev/null
+++ b/application/tables/ConfigFileDiffTable.php
@@ -0,0 +1,151 @@
+<?php
+
+namespace Icinga\Module\Director\Tables;
+
+use Icinga\Exception\ProgrammingError;
+use Icinga\Module\Director\Web\Table\QuickTable;
+use Icinga\Module\Director\Util;
+
+class ConfigFileDiffTable extends QuickTable
+{
+    protected $leftChecksum;
+
+    protected $rightChecksum;
+
+    public function getColumns()
+    {
+        throw new ProgrammingError('Accessing getColumns() is not supported');
+    }
+
+    protected function listTableClasses()
+    {
+        return array_merge(array('config-diff'), parent::listTableClasses());
+    }
+
+    protected function getRowClasses($row)
+    {
+        return 'file-' . $row->file_action;
+    }
+
+    protected function getActionUrl($row)
+    {
+        $params = array('file_path' => $row->file_path);
+
+        if ($row->file_checksum_left === $row->file_checksum_right) {
+            $params['config_checksum'] = $row->config_checksum_right;
+        } elseif ($row->file_checksum_left === null) {
+            $params['config_checksum'] = $row->config_checksum_right;
+        } elseif ($row->file_checksum_right === null) {
+            $params['config_checksum'] = $row->config_checksum_left;
+        } else {
+            $params['left']  = $row->config_checksum_left;
+            $params['right'] = $row->config_checksum_right;
+            return $this->url('director/config/filediff', $params);
+        }
+
+        return $this->url('director/config/file', $params);
+    }
+
+    public function setLeftChecksum($checksum)
+    {
+        $this->leftChecksum = $checksum;
+        return $this;
+    }
+
+    public function setRightChecksum($checksum)
+    {
+        $this->rightChecksum = $checksum;
+        return $this;
+    }
+
+    public function getTitles()
+    {
+        $view = $this->view();
+        return array(
+            'file_action' => $view->translate('Action'),
+            'file_path'   => $view->translate('File'),
+        );
+    }
+
+    public function count()
+    {
+        $db = $this->connection()->getConnection();
+        $query = clone($this->getBaseQuery());
+        $query->reset('order');
+        $this->applyFiltersToQuery($query);
+        return $db->fetchOne($db->select()->from(
+            array('cntsub' => $query),
+            array('cnt' => 'COUNT(*)')
+        ));
+    }
+
+    public function fetchData()
+    {
+        $db = $this->connection()->getConnection();
+        $query = $this->getBaseQuery();
+
+        if ($this->hasLimit() || $this->hasOffset()) {
+            $query->limit($this->getLimit(), $this->getOffset());
+        }
+
+        $this->applyFiltersToQuery($query);
+
+        return $db->fetchAll($query);
+    }
+
+    public function getBaseQuery()
+    {
+        $conn = $this->connection();
+        $db = $conn->getConnection();
+
+        $left = $db->select()
+            ->from(
+                array('cfl' => 'director_generated_config_file'),
+                array(
+                    'file_path' => 'COALESCE(cfl.file_path, cfr.file_path)',
+                    'config_checksum_left'  => $conn->dbHexFunc('cfl.config_checksum'),
+                    'config_checksum_right' => $conn->dbHexFunc('cfr.config_checksum'),
+                    'file_checksum_left'    => $conn->dbHexFunc('cfl.file_checksum'),
+                    'file_checksum_right'   => $conn->dbHexFunc('cfr.file_checksum'),
+                    'file_action'           => '(CASE WHEN cfr.config_checksum IS NULL'
+                        . " THEN 'removed' WHEN cfl.file_checksum = cfr.file_checksum"
+                        . " THEN 'unmodified' ELSE 'modified' END)",
+                )
+            )->joinLeft(
+                array('cfr' => 'director_generated_config_file'),
+                $db->quoteInto(
+                    'cfl.file_path = cfr.file_path AND cfr.config_checksum = ?',
+                    $conn->quoteBinary(Util::hex2binary($this->rightChecksum))
+                ),
+                array()
+            )->where(
+                'cfl.config_checksum = ?',
+                $conn->quoteBinary(Util::hex2binary($this->leftChecksum))
+            );
+
+        $right = $db->select()
+            ->from(
+                array('cfl' => 'director_generated_config_file'),
+                array(
+                    'file_path' => 'COALESCE(cfr.file_path, cfl.file_path)',
+                    'config_checksum_left'  => $conn->dbHexFunc('cfl.config_checksum'),
+                    'config_checksum_right' => $conn->dbHexFunc('cfr.config_checksum'),
+                    'file_checksum_left'    => $conn->dbHexFunc('cfl.file_checksum'),
+                    'file_checksum_right'   => $conn->dbHexFunc('cfr.file_checksum'),
+                    'file_action'           => "('created')",
+                )
+            )->joinRight(
+                array('cfr' => 'director_generated_config_file'),
+                $db->quoteInto(
+                    'cfl.file_path = cfr.file_path AND cfl.config_checksum = ?',
+                    $conn->quoteBinary(Util::hex2binary($this->leftChecksum))
+                ),
+                array()
+            )->where(
+                'cfr.config_checksum = ?',
+                $conn->quoteBinary(Util::hex2binary($this->rightChecksum))
+            )->where('cfl.file_checksum IS NULL');
+
+        return $db->select()->union(array($left, $right))->order('file_path');
+    }
+}
diff --git a/application/views/scripts/config/diff.phtml b/application/views/scripts/config/diff.phtml
new file mode 100644
index 00000000..d8bf64c5
--- /dev/null
+++ b/application/views/scripts/config/diff.phtml
@@ -0,0 +1,31 @@
+<div class="controls">
+<?= $this->tabs ?>
+<h1><?= $this->escape($this->title) ?></h1>
+<span class="action-links" data-base-target="_next">
+<?= $this->addLink ?>
+</span>
+<form action="<?= $this->url ?>" method="GET">
+<?= $this->formSelect(
+    'left',
+    $this->leftSum,
+    array('class' => 'autosubmit'),
+    array(null => $this->translate('- please choose -')) + $this->configs
+)
+?>
+<?= $this->formSelect(
+    'right',
+    $this->rightSum,
+    array('class' => 'autosubmit'),
+    array(null => $this->translate('- please choose -')) + $this->configs
+)
+?>
+</form>
+</div>
+
+<div class="content" data-base-target="_next">
+<?php if (count($this->table)): ?>
+<div>
+<?= $this->table->render() ?>
+</div>
+<?php endif ?>
+</div>
diff --git a/application/views/scripts/config/filediff.phtml b/application/views/scripts/config/filediff.phtml
new file mode 100644
index 00000000..14e52d73
--- /dev/null
+++ b/application/views/scripts/config/filediff.phtml
@@ -0,0 +1,11 @@
+<div class="controls">
+<?= $this->tabs ?>
+<h1><?= $this->escape($this->title) ?></h1>
+<span class="action-links" data-base-target="_next">
+<?= $this->addLink ?>
+</span>
+</div>
+
+<div class="content" data-base-target="_next">
+<?= $this->output ?>
+</div>
diff --git a/public/css/module.less b/public/css/module.less
index 734d6021..c7c7663d 100644
--- a/public/css/module.less
+++ b/public/css/module.less
@@ -975,6 +975,50 @@ table.activity-log {
     }
 }
 
+table.config-diff {
+
+    tr th:first-child {
+        padding-left: 2em;
+    }
+
+    tr td:first-child {
+        padding-left: 2em;
+        &::before {
+            font-family: 'ifont';
+            // icon-help:
+            content: '\e85b';
+            float: left;
+            font-weight: bold;
+            margin-left: -1.5em;
+            line-height: 1.5em;
+        }
+    }
+
+    tr.file-unmodified td:first-child::before {
+        // icon-ok
+        color: @color-ok;
+        content: '\e803';
+    }
+
+    tr.file-created td:first-child::before {
+        // icon-plus
+        color: @color-pending;
+        content: '\e805';
+    }
+
+    tr.file-removed td:first-child::before {
+        // icon-cancel
+        color: @color-critical;
+        content: '\e804';
+    }
+
+    tr.file-modified td:first-child::before {
+        // icon-flapping
+        color: @color-warning;
+        content: '\e85d';
+    }
+}
+
 .tree li a {
   display: inline-block;
   padding-left: 2.4em;