diff --git a/core/lib/Drupal/Core/Config/ConfigImporter.php b/core/lib/Drupal/Core/Config/ConfigImporter.php
index 5cc1a95..ada5841 100644
--- a/core/lib/Drupal/Core/Config/ConfigImporter.php
+++ b/core/lib/Drupal/Core/Config/ConfigImporter.php
@@ -8,7 +8,10 @@
 namespace Drupal\Core\Config;
 
 use Drupal\Core\Config\ConfigEvents;
+use Drupal\Core\Config\Entity\ConfigStorageControllerInterface;
+use Drupal\Core\Config\Entity\ImportableEntityStorageInterface;
 use Drupal\Core\DependencyInjection\DependencySerialization;
+use Drupal\Core\Entity\EntityStorageException;
 use Drupal\Core\Lock\LockBackendInterface;
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 
@@ -292,14 +295,15 @@ protected function importConfig($op, $name) {
    * @param string $name
    *   The name of the configuration to process.
    *
+   * @throws \Drupal\Core\Entity\EntityStorageException
+   *   Thrown if the data is owned by an entity type, but the entity storage
+   *   does not support imports.
+   *
    * @return bool
    *   TRUE if the configuration was imported as a configuration entity. FALSE
    *   otherwise.
    */
   protected function importInvokeOwner($op, $name) {
-    // Call to the configuration entity's storage controller to handle the
-    // configuration change.
-    $handled_by_module = FALSE;
     // Validate the configuration object name before importing it.
     // Config::validateName($name);
     if ($entity_type = $this->configManager->getEntityTypeIdByName($name)) {
@@ -315,9 +319,13 @@ protected function importInvokeOwner($op, $name) {
       }
 
       $method = 'import' . ucfirst($op);
-      $handled_by_module = $this->configManager->getEntityManager()->getStorageController($entity_type)->$method($name, $new_config, $old_config);
-    }
-    if (!empty($handled_by_module)) {
+      $entity_storage = $this->configManager->getEntityManager()->getStorageController($entity_type);
+      // Call to the configuration entity's storage controller to handle the
+      // configuration change.
+      if (!($entity_storage instanceof ImportableEntityStorageInterface)) {
+        throw new EntityStorageException('The entity storage does not support imports');
+      }
+      $entity_storage->$method($name, $new_config, $old_config);
       $this->setProcessed($op, $name);
       return TRUE;
     }
diff --git a/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
index 8a26ec0..84a4384 100644
--- a/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
+++ b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
@@ -35,7 +35,7 @@
  *   after the config_prefix in a config name forms the entity ID. Additional or
  *   custom suffixes are not possible.
  */
-class ConfigStorageController extends EntityStorageControllerBase implements ConfigStorageControllerInterface {
+class ConfigStorageController extends EntityStorageControllerBase implements ConfigStorageControllerInterface, ImportableEntityStorageInterface {
 
   /**
    * The UUID service.
diff --git a/core/lib/Drupal/Core/Config/Entity/ConfigStorageControllerInterface.php b/core/lib/Drupal/Core/Config/Entity/ConfigStorageControllerInterface.php
index 4ffe876..e479b7f 100644
--- a/core/lib/Drupal/Core/Config/Entity/ConfigStorageControllerInterface.php
+++ b/core/lib/Drupal/Core/Config/Entity/ConfigStorageControllerInterface.php
@@ -16,51 +16,6 @@
 interface ConfigStorageControllerInterface extends EntityStorageControllerInterface {
 
   /**
-   * Create configuration upon synchronizing configuration changes.
-   *
-   * This callback is invoked when configuration is synchronized between storages
-   * and allows a module to take over the synchronization of configuration data.
-   *
-   * @param string $name
-   *   The name of the configuration object.
-   * @param \Drupal\Core\Config\Config $new_config
-   *   A configuration object containing the new configuration data.
-   * @param \Drupal\Core\Config\Config $old_config
-   *   A configuration object containing the old configuration data.
-   */
-  public function importCreate($name, Config $new_config, Config $old_config);
-
-  /**
-   * Updates configuration upon synchronizing configuration changes.
-   *
-   * This callback is invoked when configuration is synchronized between storages
-   * and allows a module to take over the synchronization of configuration data.
-   *
-   * @param string $name
-   *   The name of the configuration object.
-   * @param \Drupal\Core\Config\Config $new_config
-   *   A configuration object containing the new configuration data.
-   * @param \Drupal\Core\Config\Config $old_config
-   *   A configuration object containing the old configuration data.
-   */
-  public function importUpdate($name, Config $new_config, Config $old_config);
-
-  /**
-   * Delete configuration upon synchronizing configuration changes.
-   *
-   * This callback is invoked when configuration is synchronized between storages
-   * and allows a module to take over the synchronization of configuration data.
-   *
-   * @param string $name
-   *   The name of the configuration object.
-   * @param \Drupal\Core\Config\Config $new_config
-   *   A configuration object containing the new configuration data.
-   * @param \Drupal\Core\Config\Config $old_config
-   *   A configuration object containing the old configuration data.
-   */
-  public function importDelete($name, Config $new_config, Config $old_config);
-
-  /**
    * Returns the config prefix used by the configuration entity type.
    *
    * @return string
diff --git a/core/lib/Drupal/Core/Config/Entity/ImportableEntityStorageInterface.php b/core/lib/Drupal/Core/Config/Entity/ImportableEntityStorageInterface.php
new file mode 100644
index 0000000..6aca4df
--- /dev/null
+++ b/core/lib/Drupal/Core/Config/Entity/ImportableEntityStorageInterface.php
@@ -0,0 +1,56 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Config\Entity\ImportableEntityStorageInterface.
+ */
+
+namespace Drupal\Core\Config\Entity;
+
+use Drupal\Core\Config\Config;
+
+/**
+ * Provides an interface for responding to configuration imports.
+ *
+ * When configuration is synchronized between storages, the entity storage must
+ * handle the synchronization of configuration data for its entity.
+ */
+interface ImportableEntityStorageInterface {
+
+  /**
+   * Creates entities upon synchronizing configuration changes.
+   *
+   * @param string $name
+   *   The name of the configuration object.
+   * @param \Drupal\Core\Config\Config $new_config
+   *   A configuration object containing the new configuration data.
+   * @param \Drupal\Core\Config\Config $old_config
+   *   A configuration object containing the old configuration data.
+   */
+  public function importCreate($name, Config $new_config, Config $old_config);
+
+  /**
+   * Updates entities upon synchronizing configuration changes.
+   *
+   * @param string $name
+   *   The name of the configuration object.
+   * @param \Drupal\Core\Config\Config $new_config
+   *   A configuration object containing the new configuration data.
+   * @param \Drupal\Core\Config\Config $old_config
+   *   A configuration object containing the old configuration data.
+   */
+  public function importUpdate($name, Config $new_config, Config $old_config);
+
+  /**
+   * Delete entities upon synchronizing configuration changes.
+   *
+   * @param string $name
+   *   The name of the configuration object.
+   * @param \Drupal\Core\Config\Config $new_config
+   *   A configuration object containing the new configuration data.
+   * @param \Drupal\Core\Config\Config $old_config
+   *   A configuration object containing the old configuration data.
+   */
+  public function importDelete($name, Config $new_config, Config $old_config);
+
+}