diff --git a/core/lib/Drupal/Core/Entity/EntityManager.php b/core/lib/Drupal/Core/Entity/EntityManager.php
index 312c7d039e31d84ad6345a0439236987f6555b5a..9a52464d7daec351170c42595bdc2242c75645e4 100644
--- a/core/lib/Drupal/Core/Entity/EntityManager.php
+++ b/core/lib/Drupal/Core/Entity/EntityManager.php
@@ -489,13 +489,23 @@ public function getFieldDefinitions($entity_type, $bundle = NULL) {
         $hooks = array('entity_field_info', $entity_type . '_field_info');
         $this->moduleHandler->alter($hooks, $this->entityFieldInfo[$entity_type], $entity_type);
 
-        // Enforce fields to be multiple by default.
-        foreach ($this->entityFieldInfo[$entity_type]['definitions'] as &$definition) {
-          $definition['list'] = TRUE;
-        }
-        foreach ($this->entityFieldInfo[$entity_type]['optional'] as &$definition) {
-          $definition['list'] = TRUE;
+        // Enforce fields to be multiple and untranslatable by default.
+        $entity_info = $this->getDefinition($entity_type);
+        $keys = array_intersect_key(array_filter($entity_info['entity_keys']), array_flip(array('id', 'revision', 'uuid', 'bundle')));
+        $untranslatable_fields = array_flip(array('langcode') + $keys);
+        foreach (array('definitions', 'optional') as $key) {
+          foreach ($this->entityFieldInfo[$entity_type][$key] as $name => &$definition) {
+            $definition['list'] = TRUE;
+            // Ensure ids and langcode fields are never made translatable.
+            if (isset($untranslatable_fields[$name]) && !empty($definition['translatable'])) {
+              throw new \LogicException(format_string('The @field field cannot be translatable.', array('@field' => $definition['label'])));
+            }
+            if (!isset($definition['translatable'])) {
+              $definition['translatable'] = FALSE;
+            }
+          }
         }
+
         $this->cache->set($cid, $this->entityFieldInfo[$entity_type], CacheBackendInterface::CACHE_PERMANENT, array('entity_info' => TRUE, 'entity_field_info' => TRUE));
       }
     }
diff --git a/core/modules/content_translation/content_translation.admin.inc b/core/modules/content_translation/content_translation.admin.inc
index d896918f2fda3c088f2a8795ef08f31efd9bb2ff..b2a83b14edc53dd0b7dc60b55c067aa13021ca55 100644
--- a/core/modules/content_translation/content_translation.admin.inc
+++ b/core/modules/content_translation/content_translation.admin.inc
@@ -8,6 +8,7 @@
 use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\Field\FieldDefinitionInterface;
 use Drupal\Core\Language\Language;
+use Drupal\field\Field as FieldService;
 
 /**
  * Returns a form element to configure field synchronization.
@@ -73,6 +74,7 @@ function _content_translation_form_language_content_settings_form_alter(array &$
   $form['#attached']['js'][] = array('data' => drupal_get_path('module', 'content_translation') . '/content_translation.admin.js', 'type' => 'file');
 
   $dependent_options_settings = array();
+  $entity_manager = Drupal::entityManager();
   foreach ($form['#labels'] as $entity_type => $label) {
     $entity_info = entity_get_info($entity_type);
     foreach (entity_get_bundles($entity_type) as $bundle => $bundle_info) {
@@ -84,31 +86,51 @@ function _content_translation_form_language_content_settings_form_alter(array &$
       // Only show the checkbox to enable translation if the bundles in the
       // entity might have fields and if there are fields to translate.
       if (!empty($entity_info['fieldable'])) {
-        $instances = field_info_instances($entity_type, $bundle);
-        if ($instances) {
+        $fields = $entity_manager->getFieldDefinitions($entity_type, $bundle);
+        if ($fields) {
           $form['settings'][$entity_type][$bundle]['translatable'] = array(
             '#type' => 'checkbox',
             '#title' => $bundle,
             '#default_value' => content_translation_enabled($entity_type, $bundle),
           );
 
-          // @todo Exploit field definitions once all core entities and field
-          // types are migrated to the Entity Field API.
-          foreach ($instances as $field_name => $instance) {
-            $form['settings'][$entity_type][$bundle]['fields'][$field_name] = array(
-              '#label' => $instance->getFieldLabel(),
-              '#type' => 'checkbox',
-              '#title' => $instance->getFieldLabel(),
-              '#default_value' => $instance->isFieldTranslatable(),
-            );
-            $column_element = content_translation_field_sync_widget($instance);
-            if ($column_element) {
-              $form['settings'][$entity_type][$bundle]['columns'][$field_name] = $column_element;
-
-              if (isset($column_element['#options']['file'])) {
-                $dependent_options_settings["settings[{$entity_type}][{$bundle}][columns][{$field_name}]"] = array('file');
+          $field_settings = content_translation_get_config($entity_type, $bundle, 'fields');
+          foreach ($fields as $field_name => $definition) {
+            $translatable = !empty($field_settings[$field_name]);
+
+            // We special case Field API fields as they always natively support
+            // translation.
+            // @todo Remove this special casing as soon as configurable and
+            //   base field definitions are "unified".
+            if (!empty($definition['configurable']) && ($field = FieldService::fieldInfo()->getField($entity_type, $field_name))) {
+              $instance = FieldService::fieldInfo()->getInstance($entity_type, $bundle, $field_name);
+              $form['settings'][$entity_type][$bundle]['fields'][$field_name] = array(
+                '#label' => $instance->getFieldLabel(),
+                '#type' => 'checkbox',
+                '#title' => $instance->getFieldLabel(),
+                '#default_value' => $translatable,
+              );
+              $column_element = content_translation_field_sync_widget($instance);
+              if ($column_element) {
+                $form['settings'][$entity_type][$bundle]['columns'][$field_name] = $column_element;
+
+                // @todo This should not concern only files.
+                if (isset($column_element['#options']['file'])) {
+                  $dependent_options_settings["settings[{$entity_type}][{$bundle}][columns][{$field_name}]"] = array('file');
+                }
               }
             }
+            // Instead we need to rely on field definitions to determine whether
+            // fields support translation. Whether they are actually enabled is
+            // determined through our settings. As a consequence only fields
+            // that support translation can be enabled or disabled.
+            elseif (isset($field_settings[$field_name]) || !empty($definition['translatable'])) {
+              $form['settings'][$entity_type][$bundle]['fields'][$field_name] = array(
+                '#label' => $definition['label'],
+                '#type' => 'checkbox',
+                '#default_value' => $translatable,
+              );
+            }
           }
         }
       }
@@ -326,11 +348,11 @@ function _content_translation_update_field_translatability($settings) {
         foreach ($bundle_settings['fields'] as $field_name => $translatable) {
           // If a field is enabled for translation for at least one instance we
           // need to mark it as translatable.
-          $fields[$entity_type][$field_name] = $translatable || !empty($fields[$entity_type][$field_name]);
+          if (FieldService::fieldInfo()->getField($entity_type, $field_name)) {
+            $fields[$entity_type][$field_name] = $translatable || !empty($fields[$entity_type][$field_name]);
+          }
         }
       }
-      // @todo Store non-configurable field settings to be able to alter their
-      //   definition afterwards.
     }
   }
 
diff --git a/core/modules/content_translation/content_translation.module b/core/modules/content_translation/content_translation.module
index 20d72edaabc816e20cf467964b0437c253af2dc9..fe80ac69a13a7d05e4e50c5e17bea6efb16f1dd6 100644
--- a/core/modules/content_translation/content_translation.module
+++ b/core/modules/content_translation/content_translation.module
@@ -126,6 +126,33 @@ function content_translation_entity_bundle_info_alter(&$bundles) {
   }
 }
 
+/**
+ * Implements hook_entity_field_info_alter().
+ */
+function content_translation_entity_field_info_alter(&$info, $entity_type) {
+  $translation_settings = config('content_translation.settings')->get($entity_type);
+
+  if ($translation_settings) {
+    // Currently field translatability is defined per-field but we may want to
+    // make it per-instance instead, so leaving the possibility open for further
+    // easier refactoring.
+    $fields = array();
+    foreach ($translation_settings as $bundle => $settings) {
+      $fields += !empty($settings['content_translation']['fields']) ? $settings['content_translation']['fields'] : array();
+    }
+
+    $keys = array('definitions', 'optional');
+    foreach ($fields as $name => $translatable) {
+      foreach ($keys as $key) {
+        if (isset($info[$key][$name])) {
+          $info[$key][$name]['translatable'] = (bool) $translatable;
+          break;
+        }
+      }
+    }
+  }
+}
+
 /**
  * Implements hook_menu().
  */
@@ -987,6 +1014,11 @@ function content_translation_save_settings($settings) {
         // Store whether a bundle has translation enabled or not.
         content_translation_set_config($entity_type, $bundle, 'enabled', $bundle_settings['translatable']);
 
+        // Store whether fields are translatable or not.
+        if (!empty($bundle_settings['fields'])) {
+          content_translation_set_config($entity_type, $bundle, 'fields', $bundle_settings['fields']);
+        }
+
         // Store whether fields have translation enabled or not.
         if (!empty($bundle_settings['columns'])) {
           foreach ($bundle_settings['columns'] as $field_name => $column_settings) {
diff --git a/core/modules/content_translation/lib/Drupal/content_translation/Tests/ContentTranslationSettingsTest.php b/core/modules/content_translation/lib/Drupal/content_translation/Tests/ContentTranslationSettingsTest.php
index 7e4664f96460828d2fb131138adcc5dd9f851859..127f7eaad200c71b35b506cd98983e7637a782e6 100644
--- a/core/modules/content_translation/lib/Drupal/content_translation/Tests/ContentTranslationSettingsTest.php
+++ b/core/modules/content_translation/lib/Drupal/content_translation/Tests/ContentTranslationSettingsTest.php
@@ -20,7 +20,7 @@ class ContentTranslationSettingsTest extends WebTestBase {
    *
    * @var array
    */
-  public static $modules = array('language', 'content_translation', 'comment', 'field_ui');
+  public static $modules = array('language', 'content_translation', 'node', 'comment', 'field_ui');
 
   public static function getInfo() {
     return array(
@@ -114,6 +114,17 @@ function testSettingsUI() {
     $this->drupalPostForm('admin/structure/types/manage/article', $edit, t('Save content type'));
     $this->drupalGet('admin/structure/types/manage/article');
     $this->assertFieldChecked('edit-language-configuration-content-translation');
+
+    // Test that the title field of nodes is available in the settings form.
+    $edit = array(
+      'entity_types[node]' => TRUE,
+      'settings[node][article][settings][language][langcode]' => 'current_interface',
+      'settings[node][article][settings][language][language_show]' => TRUE,
+      'settings[node][article][translatable]' => TRUE,
+      'settings[node][article][fields][title]' => TRUE
+    );
+    $this->assertSettings('node', NULL, TRUE, $edit);
+
   }
 
   /**
diff --git a/core/modules/content_translation/lib/Drupal/content_translation/Tests/ContentTranslationSyncImageTest.php b/core/modules/content_translation/lib/Drupal/content_translation/Tests/ContentTranslationSyncImageTest.php
index 9789dc5f2b7d378d656412c47e6b34e9d9b8588b..f97483798fb188fd1be77f8654b4f7c0772f33ec 100644
--- a/core/modules/content_translation/lib/Drupal/content_translation/Tests/ContentTranslationSyncImageTest.php
+++ b/core/modules/content_translation/lib/Drupal/content_translation/Tests/ContentTranslationSyncImageTest.php
@@ -108,10 +108,13 @@ function testImageFieldSync() {
     $this->assertNoFieldChecked('edit-settings-entity-test-mul-entity-test-mul-columns-field-test-et-ui-image-alt');
     $this->assertNoFieldChecked('edit-settings-entity-test-mul-entity-test-mul-columns-field-test-et-ui-image-title');
     $edit = array(
+      'settings[entity_test_mul][entity_test_mul][fields][field_test_et_ui_image]' => TRUE,
       'settings[entity_test_mul][entity_test_mul][columns][field_test_et_ui_image][alt]' => TRUE,
       'settings[entity_test_mul][entity_test_mul][columns][field_test_et_ui_image][title]' => TRUE,
     );
     $this->drupalPostForm('admin/config/regional/content-language', $edit, t('Save'));
+    $errors = $this->xpath('//div[contains(@class, "messages--error")]');
+    $this->assertFalse($errors, 'Settings correctly stored.');
     $this->assertFieldChecked('edit-settings-entity-test-mul-entity-test-mul-columns-field-test-et-ui-image-alt');
     $this->assertFieldChecked('edit-settings-entity-test-mul-entity-test-mul-columns-field-test-et-ui-image-title');
     $this->drupalLogin($this->translator);
diff --git a/core/modules/node/lib/Drupal/node/Entity/Node.php b/core/modules/node/lib/Drupal/node/Entity/Node.php
index 92f4f5b638395a56ee8bb8ba8489d65bc5b8d315..de94ae8b3b4cf4b8dcc1ee6aba628c8b7c80bec4 100644
--- a/core/modules/node/lib/Drupal/node/Entity/Node.php
+++ b/core/modules/node/lib/Drupal/node/Entity/Node.php
@@ -359,6 +359,7 @@ public static function baseFieldDefinitions($entity_type) {
       'property_constraints' => array(
         'value' => array('Length' => array('max' => 255)),
       ),
+      'translatable' => TRUE,
     );
     $properties['uid'] = array(
       'label' => t('User ID'),
diff --git a/core/modules/node/lib/Drupal/node/Tests/NodeTranslationUITest.php b/core/modules/node/lib/Drupal/node/Tests/NodeTranslationUITest.php
index 77c0bbd5a63b4f1bf20c95e8a5d375395dfba848..338955c5846bc55850e896ec4d1b2abc30777215 100644
--- a/core/modules/node/lib/Drupal/node/Tests/NodeTranslationUITest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/NodeTranslationUITest.php
@@ -15,11 +15,6 @@
  */
 class NodeTranslationUITest extends ContentTranslationUITest {
 
-  /**
-   * The title of the test node.
-   */
-  protected $title;
-
   /**
    * Modules to enable.
    *
@@ -38,7 +33,6 @@ public static function getInfo() {
   function setUp() {
     $this->entityType = 'node';
     $this->bundle = 'article';
-    $this->title = $this->randomName();
     parent::setUp();
     $this->drupalPlaceBlock('system_help_block', array('region' => 'content'));
   }
@@ -62,8 +56,7 @@ protected function getTranslatorPermissions() {
    * Overrides \Drupal\content_translation\Tests\ContentTranslationUITest::getNewEntityValues().
    */
   protected function getNewEntityValues($langcode) {
-    // Node title is not translatable yet, hence we use a fixed value.
-    return array('title' => $this->title) + parent::getNewEntityValues($langcode);
+    return array('title' => $this->randomName()) + parent::getNewEntityValues($langcode);
   }
 
   /**
diff --git a/core/modules/system/lib/Drupal/system/Tests/Entity/EntityTranslationTest.php b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityTranslationTest.php
index b397f2c03f455aed846744cbda10889770c451b8..e2b0d4f395a54c2d4c30921e038df39fee098cd2 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Entity/EntityTranslationTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityTranslationTest.php
@@ -9,6 +9,7 @@
 
 use Drupal\Core\Language\Language;
 use Drupal\Core\TypedData\TranslatableInterface;
+use Drupal\entity_test\Entity\EntityTestMulRev;
 
 /**
  * Tests entity translation.
@@ -492,4 +493,42 @@ function testEntityTranslationAPI() {
     $this->assertEqual($field->getLangcode(), $langcode2, 'Field object has the expected langcode.');
   }
 
+  /**
+   * Check that field translatability is handled properly.
+   */
+  function testFieldDefinitions() {
+    // Check that field translatability can be altered to be enabled or disabled
+    // in field definitions.
+    $entity_type = 'entity_test_mulrev';
+    $this->state->set('entity_test.field_definitions.translatable', array('name' => FALSE));
+    $this->entityManager->clearCachedFieldDefinitions();
+    $definitions = $this->entityManager->getFieldDefinitions($entity_type);
+    $this->assertFalse($definitions['name']['translatable'], 'Field translatability can be disabled programmatically.');
+
+    $this->state->set('entity_test.field_definitions.translatable', array('name' => TRUE));
+    $this->entityManager->clearCachedFieldDefinitions();
+    $definitions = $this->entityManager->getFieldDefinitions($entity_type);
+    $this->assertTrue($definitions['name']['translatable'], 'Field translatability can be enabled programmatically.');
+
+    // Check that field translatability is disabled by default.
+    $base_field_definitions = EntityTestMulRev::baseFieldDefinitions($entity_type);
+    $this->assertTrue(!isset($base_field_definitions['id']['translatable']), 'Translatability for the <em>id</em> field is not defined.');
+    $this->assertFalse($definitions['id']['translatable'], 'Field translatability is disabled by default.');
+
+    // Check that entity ids and langcode fields cannot be translatable.
+    foreach (array('id', 'uuid', 'revision_id', 'type', 'langcode') as $name) {
+      $this->state->set('entity_test.field_definitions.translatable', array($name => TRUE));
+      $this->entityManager->clearCachedFieldDefinitions();
+      $message = format_string('Field %field cannot be translatable.', array('%field' => $name));
+
+      try {
+        $definitions = $this->entityManager->getFieldDefinitions($entity_type);
+        $this->fail($message);
+      }
+      catch (\LogicException $e) {
+        $this->pass($message);
+      }
+    }
+  }
+
 }
diff --git a/core/modules/system/tests/modules/entity_test/entity_test.module b/core/modules/system/tests/modules/entity_test/entity_test.module
index cc8800e0cb17a83edc29ae83840ad7352dc04928..e949e5035366929a5d03186e90265b7963c36588 100644
--- a/core/modules/system/tests/modules/entity_test/entity_test.module
+++ b/core/modules/system/tests/modules/entity_test/entity_test.module
@@ -72,6 +72,17 @@ function entity_test_entity_info_alter(&$info) {
   }
 }
 
+/**
+ * Implements hook_entity_field_info_alter().
+ */
+function entity_test_entity_field_info_alter(&$info, $entity_type) {
+  if ($entity_type == 'entity_test_mulrev' && ($names = \Drupal::state()->get('entity_test.field_definitions.translatable'))) {
+    foreach ($names as $name => $value) {
+      $info['definitions'][$name]['translatable'] = $value;
+    }
+  }
+}
+
 /**
  * Creates a new bundle for entity_test entities.
  *
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermTranslationUITest.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermTranslationUITest.php
index 20becd171d918c447e778a37674ce3f275c4b3a8..99594ee538435fb9b60c047aee0bc9ffa71ae2c8 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermTranslationUITest.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermTranslationUITest.php
@@ -90,9 +90,9 @@ public function testTranslationUI() {
     // Make sure that no row was inserted for taxonomy vocabularies, which do
     // not have translations enabled.
     $rows = db_query('SELECT * FROM {content_translation}')->fetchAll();
-    $this->assertEqual(2, count($rows));
-    $this->assertEqual('taxonomy_term', $rows[0]->entity_type);
-    $this->assertEqual('taxonomy_term', $rows[1]->entity_type);
+    foreach ($rows as $row) {
+      $this->assertEqual('taxonomy_term', $row->entity_type);
+    }
   }
 
   /**