diff --git a/core/lib/Drupal/Core/Entity/EntityManager.php b/core/lib/Drupal/Core/Entity/EntityManager.php
index 4766a91..e9a3783 100644
--- a/core/lib/Drupal/Core/Entity/EntityManager.php
+++ b/core/lib/Drupal/Core/Entity/EntityManager.php
@@ -454,4 +454,19 @@ public function clearCachedFieldDefinitions() {
     $this->cache->deleteTags(array('entity_field_info' => TRUE));
   }
 
+  /**
+   * Build a list of entity type options.
+   *
+   * @return array
+   *   Keys are plugin IDs and values are plugin labels.
+   */
+  function options() {
+    $options = array();
+    foreach ($this->getDefinitions() as $entity_type => $definition) {
+      $options[$entity_type] = $definition['label'];
+    }
+
+    return $options;
+  }
+
 }
diff --git a/core/lib/Drupal/Core/Entity/Plugin/DataType/EntityReferenceItem.php b/core/lib/Drupal/Core/Entity/Plugin/DataType/EntityReferenceItem.php
index 3e67f7e..bf529a0 100644
--- a/core/lib/Drupal/Core/Entity/Plugin/DataType/EntityReferenceItem.php
+++ b/core/lib/Drupal/Core/Entity/Plugin/DataType/EntityReferenceItem.php
@@ -49,11 +49,12 @@ public function getPropertyDefinitions() {
 
     if (!isset(static::$propertyDefinitions[$key])) {
       static::$propertyDefinitions[$key]['target_id'] = array(
-        // @todo: Lookup the entity type's ID data type and use it here.
-        'type' => 'integer',
+        'type' => 'string',
         'label' => t('Entity ID'),
         'constraints' => array(
-          'Range' => array('min' => 0),
+          'Length' => array(
+            'min' => 0,
+          ),
         ),
       );
       static::$propertyDefinitions[$key]['entity'] = array(
diff --git a/core/modules/entity_reference/entity_reference.install b/core/modules/entity_reference/entity_reference.install
index c40d3ea..536d5e7 100644
--- a/core/modules/entity_reference/entity_reference.install
+++ b/core/modules/entity_reference/entity_reference.install
@@ -14,9 +14,8 @@ function entity_reference_field_schema($field) {
     'columns' => array(
       'target_id' => array(
         'description' => 'The ID of the target entity.',
-        'type' => 'int',
-        'unsigned' => TRUE,
-        'not null' => TRUE,
+        'type' => 'varchar',
+        'length' => 255,
       ),
       'revision_id' => array(
         'description' => 'The revision ID of the target entity.',
@@ -30,19 +29,5 @@ function entity_reference_field_schema($field) {
     ),
   );
 
-  // Create a foreign key to the target entity type base type.
-  $entity_manager = Drupal::service('plugin.manager.entity');
-  if (is_subclass_of($entity_manager->getControllerClass($field['settings']['target_type'], 'storage'), 'Drupal\Core\Entity\DatabaseStorageController')) {
-    $entity_info = $entity_manager->getDefinition($field['settings']['target_type']);
-
-    $base_table = $entity_info['base_table'];
-    $id_column = $entity_info['entity_keys']['id'];
-
-    $schema['foreign keys'][$base_table] = array(
-      'table' => $base_table,
-      'columns' => array('target_id' => $id_column),
-    );
-  }
-
   return $schema;
 }
diff --git a/core/modules/entity_reference/entity_reference.module b/core/modules/entity_reference/entity_reference.module
index 54a7bac..c2800e6 100644
--- a/core/modules/entity_reference/entity_reference.module
+++ b/core/modules/entity_reference/entity_reference.module
@@ -133,21 +133,10 @@ function entity_reference_field_validate(EntityInterface $entity = NULL, $field,
  * Implements hook_field_settings_form().
  */
 function entity_reference_field_settings_form($field, $instance) {
-  // Select the target entity type.
-  $entity_type_options = array();
-  foreach (entity_get_info() as $entity_type => $entity_info) {
-    // @todo As the database schema can currently only store numeric IDs of
-    // referenced entities and configuration entities have string IDs, prevent
-    // configuration entities from being referenced.
-    if (!is_subclass_of($entity_info['class'], '\Drupal\Core\Config\Entity\ConfigEntityInterface')) {
-      $entity_type_options[$entity_type] = $entity_info['label'];
-    }
-  }
-
   $form['target_type'] = array(
     '#type' => 'select',
     '#title' => t('Type of item to reference'),
-    '#options' => $entity_type_options,
+    '#options' => Drupal::entityManager()->options(),
     '#default_value' => $field['settings']['target_type'],
     '#required' => TRUE,
     '#disabled' => $field->hasData(),
diff --git a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceAdminTest.php b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceAdminTest.php
index 932f55f..0ccffc6 100644
--- a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceAdminTest.php
+++ b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceAdminTest.php
@@ -74,6 +74,10 @@ public function testFieldAdminHandler() {
 
     // Node should be selected by default.
     $this->assertFieldByName('field[settings][target_type]', 'node');
+    $entity_manager = $this->container->get('plugin.manager.entity');
+    foreach ($entity_manager->getDefinitions() as $plugin_id => $definition) {
+      $this->assertFieldByXPath("//select[@name='field[settings][target_type]']/option[@value='" . $plugin_id . "']");
+    }
 
     // Second step: 'Instance settings' form.
     $this->drupalPost(NULL, array(), t('Save field settings'));
diff --git a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceItemTest.php b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceItemTest.php
index 8c17fd6..34b58b9 100644
--- a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceItemTest.php
+++ b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceItemTest.php
@@ -41,96 +41,81 @@ public function setUp() {
     $this->installSchema('taxonomy', 'taxonomy_term_data');
     $this->installSchema('taxonomy', 'taxonomy_term_hierarchy');
 
-    $vocabulary = entity_create('taxonomy_vocabulary', array(
+    $this->vocabulary = entity_create('taxonomy_vocabulary', array(
       'name' => $this->randomName(),
       'vid' => drupal_strtolower($this->randomName()),
       'langcode' => Language::LANGCODE_NOT_SPECIFIED,
     ));
-    $vocabulary->save();
+    $this->vocabulary->save();
 
     $this->term = entity_create('taxonomy_term', array(
       'name' => $this->randomName(),
-      'vid' => $vocabulary->id(),
+      'vid' => $this->vocabulary->id(),
       'langcode' => Language::LANGCODE_NOT_SPECIFIED,
     ));
     $this->term->save();
 
     // Use the util to create an instance.
-    entity_reference_create_instance('entity_test', 'entity_test', 'field_test_taxonomy', 'Test entity reference', 'taxonomy_term');
+    entity_reference_create_instance('entity_test', 'entity_test', 'field_test_taxonomy_term', 'Test entity term reference', 'taxonomy_term');
+    entity_reference_create_instance('entity_test', 'entity_test', 'field_test_taxonomy_vocabulary', 'Test entity vocabulary reference', 'taxonomy_vocabulary');
   }
 
   /**
    * Tests using entity fields of the entity reference field type.
    */
   public function testEntityReferenceItem() {
-    $tid = $this->term->id();
-
-    // Just being able to create the entity like this verifies a lot of code.
-    $entity = entity_create('entity_test', array());
-    $entity->field_test_taxonomy->target_id = $tid;
-    $entity->name->value = $this->randomName();
-    $entity->save();
-
-    $entity = entity_load('entity_test', $entity->id());
-    $this->assertTrue($entity->field_test_taxonomy instanceof FieldInterface, 'Field implements interface.');
-    $this->assertTrue($entity->field_test_taxonomy[0] instanceof FieldItemInterface, 'Field item implements interface.');
-    $this->assertEqual($entity->field_test_taxonomy->target_id, $tid);
-    $this->assertEqual($entity->field_test_taxonomy->entity->name->value, $this->term->name->value);
-    $this->assertEqual($entity->field_test_taxonomy->entity->id(), $tid);
-    $this->assertEqual($entity->field_test_taxonomy->entity->uuid(), $this->term->uuid());
-
-    // Change the name of the term via the reference.
-    $new_name = $this->randomName();
-    $entity->field_test_taxonomy->entity->name = $new_name;
-    $entity->field_test_taxonomy->entity->save();
-    // Verify it is the correct name.
-    $term = entity_load('taxonomy_term', $tid);
-    $this->assertEqual($term->name->value, $new_name);
-
-    // Make sure the computed term reflects updates to the term id.
-    $term2 = entity_create('taxonomy_term', array(
-      'name' => $this->randomName(),
-      'vid' => $this->term->bundle(),
-      'langcode' => Language::LANGCODE_NOT_SPECIFIED,
-    ));
-    $term2->save();
+    $entity_manager = $this->container->get('plugin.manager.entity');
 
-    $entity->field_test_taxonomy->target_id = $term2->id();
-    $this->assertEqual($entity->field_test_taxonomy->entity->id(), $term2->id());
-    $this->assertEqual($entity->field_test_taxonomy->entity->name->value, $term2->name->value);
-
-    // Delete terms so we have nothing to reference and try again
-    $term->delete();
-    $term2->delete();
-    $entity = entity_create('entity_test', array('name' => $this->randomName()));
-    $entity->save();
-  }
-
-  /**
-   * Tests foreign key support.
-   */
-  public function testEntityReferenceFieldSchema() {
-    $field = field_info_field('field_test_taxonomy');
-    $foreign_key_column_name = 'target_id';
-
-    // Grab the SQL schema and verify that the 'foreign keys' are present.
-    $schemas = _field_sql_storage_schema($field);
-    $schema = $schemas[_field_sql_storage_tablename($field)];
-    $this->assertEqual(count($schema['foreign keys']), 1, 'There is 1 foreign key in the schema.');
-
-    $foreign_key = reset($schema['foreign keys']);
-    $foreign_key_column = _field_sql_storage_columnname($field['field_name'], $foreign_key_column_name);
-    $this->assertEqual($foreign_key['table'], 'taxonomy_term_data', 'Foreign key table name preserved in the schema.');
-    $this->assertEqual($foreign_key['columns'][$foreign_key_column], 'tid', 'Foreign key column name preserved in the schema.');
-
-    // Create a field that references a config entity type and check that no
-    // foreign key is present.
-    $field_name = 'field_test_vocabulary';
-    entity_reference_create_instance('entity_test', 'entity_test', $field_name, 'Test vocabulary reference', 'taxonomy_vocabulary');
-    $field = field_info_field($field_name);
-
-    $schemas = _field_sql_storage_schema($field);
-    $schema = $schemas[_field_sql_storage_tablename($field)];
-    $this->assertFalse(isset($schema['foreign keys']), 'There is no foreign key in the schema.');
+    // Test a content and a configuration entity.
+    $fields = array(
+      'field_test_taxonomy_term' => $this->term,
+      'field_test_taxonomy_vocabulary' => $this->vocabulary,
+    );
+    foreach ($fields as $field_name => $referenced_entity) {
+      $referenced_entity_definition = $entity_manager->getDefinition($referenced_entity->entityType());
+
+      // Just being able to create the entity like this verifies a lot of code.
+      $entity = entity_create('entity_test', array());
+      $entity->get($field_name)->target_id = $referenced_entity->id();
+      $entity->name->value = $this->randomName();
+      $entity->save();
+
+      $entity = entity_load('entity_test', $entity->id());
+      $this->assertTrue($entity->get($field_name) instanceof FieldInterface, 'Field implements interface.');
+      $this->assertTrue($entity->get($field_name)[0] instanceof FieldItemInterface, 'Field item implements interface.');
+      $this->assertEqual($entity->get($field_name)->target_id, $referenced_entity->id());
+      $this->assertEqual($entity->get($field_name)->entity->label(), $referenced_entity->label());
+      $this->assertEqual($entity->get($field_name)->entity->id(), $referenced_entity->id());
+      $this->assertEqual($entity->get($field_name)->entity->uuid(), $referenced_entity->uuid());
+
+      // Change the label of the referenced entity via the reference.
+      $new_name = $this->randomName();
+      $label_property = $referenced_entity_definition['entity_keys']['label'];
+      $entity->get($field_name)->entity->$label_property = $new_name;
+      $entity->get($field_name)->entity->save();
+      // Verify it is the correct label.
+      $referenced_entity = entity_load($referenced_entity->entityType(), $referenced_entity->id());
+      $this->assertEqual($referenced_entity->name->value, $new_name);
+
+      // Make sure the computed referenced entity reflects updates to the
+      // reference ID.
+      $referenced_entity2 = entity_create($referenced_entity->entityType(), array(
+        'name' => $this->randomName(),
+        $referenced_entity_definition['entity_keys']['bundle'] => $referenced_entity->bundle(),
+        'langcode' => Language::LANGCODE_NOT_SPECIFIED,
+      ));
+      $referenced_entity2->save();
+
+      $entity->get($field_name)->target_id = $referenced_entity2->id();
+      $this->assertEqual($entity->get($field_name)->entity->id(), $referenced_entity2->id());
+      $this->assertEqual($entity->get($field_name)->entity->label(), $referenced_entity2->label());
+
+      // Delete the referenced entities so we have nothing to reference and try
+      // again
+      $referenced_entity->delete();
+      $referenced_entity2->delete();
+      $entity = entity_create('entity_test', array('name' => $this->randomName()));
+      $entity->save();
+    }
   }
 }