diff -u b/core/modules/config/lib/Drupal/config/Form/ConfigSync.php b/core/modules/config/lib/Drupal/config/Form/ConfigSync.php
--- b/core/modules/config/lib/Drupal/config/Form/ConfigSync.php
+++ b/core/modules/config/lib/Drupal/config/Form/ConfigSync.php
@@ -7,14 +7,18 @@
 
 namespace Drupal\config\Form;
 
-use Drupal\Core\ControllerInterface;
-use Drupal\Core\Database\Connection;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+use Drupal\Core\Controller\ControllerInterface;
 use Drupal\Core\Form\FormInterface;
 use Drupal\Core\Config\StorageInterface;
-use Drupal\Core\Ajax\AjaxResponse;
-use Drupal\Core\Ajax\OpenModalDialogCommand;
 use Drupal\Core\Lock\LockBackendInterface;
-use Symfony\Component\DependencyInjection\ContainerInterface;
+use Drupal\Core\Config\StorageComparer;
+use Drupal\Core\Config\ConfigImporter;
+use Drupal\Core\Config\ConfigException;
+use Drupal\Core\Config\ConfigFactory;
+use \Drupal\Core\Entity\EntityManager;
 
 /**
  * Construct the storage changes in a configuration synchronization form.
@@ -22,13 +26,6 @@
 class ConfigSync implements ControllerInterface, FormInterface {
 
   /**
-   * The database connection object.
-   *
-   * @var \Drupal\Core\Database\Connection
-   */
-  protected $database;
-
-  /**
    * The database lock object.
    *
    * @var \Drupal\Core\Lock\LockBackendInterface
@@ -50,7 +47,24 @@
   protected $targetStorage;
 
   /**
-   * Constructs a database object.
+   * Event dispatcher.
+   *
+   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
+   */
+  protected $eventDispatcher;
+
+  /**
+   * @var \Drupal\Core\Config\ConfigFactory;
+   */
+  protected $configFactory;
+
+  /**
+   * @var \Drupal\Core\Entity\EntityManager;
+   */
+  protected $entity_manager;
+
+  /**
+   * Constructs the object.
    *
    * @param \Drupal\Core\Database\Connection; $database
    *   The database object.
@@ -60,12 +74,20 @@
    *   The target storage manager.
    * @param \Drupal\Core\Lock\LockBackendInterface $lock
    *   The lock object.
+   * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $event_dispatcher
+   *   Event dispatcher.
+   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   *   Configuration object factory.
+   * @param \Drupal\Core\Entity\EntityManager
+   *   Entity manager.
    */
-  public function __construct(Connection $database, StorageInterface $sourceStorage, StorageInterface $targetStorage, LockBackendInterface $lock) {
-    $this->database = $database;
+  public function __construct(StorageInterface $sourceStorage, StorageInterface $targetStorage, LockBackendInterface $lock, EventDispatcherInterface $event_dispatcher, ConfigFactory $config_factory, EntityManager $entity_manger) {
     $this->sourceStorage = $sourceStorage;
     $this->targetStorage = $targetStorage;
     $this->lock = $lock;
+    $this->eventDispatcher = $event_dispatcher;
+    $this->configFactory = $config_factory;
+    $this->entity_manager = $entity_manger;
   }
 
   /**
@@ -73,10 +95,12 @@
    */
   public static function create(ContainerInterface $container) {
     return new static(
-      $container->get('database'),
       $container->get('config.storage.staging'),
       $container->get('config.storage'),
-      $container->get('lock')
+      $container->get('lock'),
+      $container->get('event_dispatcher'),
+      $container->get('config.factory'),
+      $container->get('plugin.manager.entity')
     );
   }
 
@@ -106,23 +130,30 @@
    * {@inheritdoc}
    */
   public function submitForm(array &$form, array &$form_state) {
-    if (!$this->lock->lockMayBeAvailable(CONFIG_IMPORT_LOCK)) {
+    $config_importer = new ConfigImporter(
+      $form_state['storage_comparer'],
+      $this->eventDispatcher,
+      $this->configFactory,
+      $this->entity_manager,
+      $this->lock
+    );
+    if ($config_importer->alreadyImporting()) {
       drupal_set_message(t('Another request may be synchronizing configuration already.'));
     }
-    else if (config_import()) {
-      // Once a sync completes, we empty the staging directory. This prevents
-      // changes from being accidentally overwritten by stray files getting
-      // imported later.
-      foreach ($this->sourceStorage->listAll() as $name) {
-        $this->sourceStorage->delete($name);
+    else{
+      try {
+        $config_importer->import();
+        drupal_flush_all_caches();
+        drupal_set_message(t('The configuration was imported successfully.'));
+      }
+      catch (ConfigException $e) {
+        // Return a negative result for UI purposes. We do not differentiate between
+        // an actual synchronization error and a failed lock, because concurrent
+        // synchronizations are an edge-case happening only when multiple developers
+        // or site builders attempt to do it without coordinating.
+        watchdog_exception('config_import', $e);
+        drupal_set_message(t('The import failed due to an error. Any errors have been logged.'), 'error');
       }
-
-      drupal_flush_all_caches();
-
-      drupal_set_message(t('The configuration was imported successfully.'));
-    }
-    else {
-      drupal_set_message(t('The import failed due to an error. Any errors have been logged.'), 'error');
     }
   }
 
@@ -142,34 +173,31 @@
    */
   private function config_admin_sync_form(array &$form, array &$form_state) {
     $source_list = $this->sourceStorage->listAll();
-    if (empty($source_list)) {
+    $config_comparer = new StorageComparer($this->sourceStorage, $this->targetStorage);
+    if (empty($source_list) || !$config_comparer->createChangelist()->hasChanges()) {
       $form['no_changes'] = array(
-        '#markup' => t('There is no configuration to import.'),
+        '#markup' => t('There are no configuration changes.'),
       );
       $form['actions']['#access'] = FALSE;
       return $form;
     }
-
-    $config_changes = config_sync_get_changes($this->sourceStorage, $this->targetStorage);
-    if (empty($config_changes)) {
-      $form['no_changes'] = array(
-        '#markup' => t('There are no configuration changes.'),
-      );
-      return $form;
+    else {
+      // Store the comparer for use in the submit.
+      $form_state['storage_comparer'] = $config_comparer;
     }
 
     // Add the AJAX library to the form for dialog support.
     $form['#attached']['library'][] = array('system', 'drupal.ajax');
 
-    foreach ($config_changes as $config_change_type => $config_files) {
+    foreach ($config_comparer->getChangelist() as $config_change_type => $config_files) {
       if (empty($config_files)) {
         continue;
       }
 
       // @todo A table caption would be more appropriate, but does not have the
-      // visual importance of a heading.
+      //   visual importance of a heading.
       $form[$config_change_type]['heading'] = array(
-        '#theme' => 'html_tag__h3',
+        '#type' => 'html_tag',
         '#tag' => 'h3',
       );
       switch ($config_change_type) {
@@ -177,7 +205,7 @@
           $form[$config_change_type]['heading']['#value'] = format_plural(count($config_files), '@count new', '@count new');
           break;
 
-        case 'change':
+        case 'update':
           $form[$config_change_type]['heading']['#value'] = format_plural(count($config_files), '@count changed', '@count changed');
           break;