diff --git a/core/modules/serialization/serialization.services.yml b/core/modules/serialization/serialization.services.yml
index 8b570c0..7b92f7a 100644
--- a/core/modules/serialization/serialization.services.yml
+++ b/core/modules/serialization/serialization.services.yml
@@ -17,6 +17,10 @@ services:
     tags:
       - { name: normalizer }
     arguments: ['@entity.manager']
+  serializer.normalizer.primitive_data:
+    class: Drupal\serialization\Normalizer\PrimitiveDataNormalizer
+    tags:
+      - { name: normalizer, priority: 20 }
   serializer.normalizer.complex_data:
     class: Drupal\serialization\Normalizer\ComplexDataNormalizer
     tags:
diff --git a/core/modules/serialization/src/Normalizer/PrimitiveDataNormalizer.php b/core/modules/serialization/src/Normalizer/PrimitiveDataNormalizer.php
new file mode 100644
index 0000000..66a3c68
--- /dev/null
+++ b/core/modules/serialization/src/Normalizer/PrimitiveDataNormalizer.php
@@ -0,0 +1,24 @@
+<?php
+
+namespace Drupal\serialization\Normalizer;
+
+/**
+ * Converts primitive data objects to their casted values.
+ */
+class PrimitiveDataNormalizer extends NormalizerBase {
+
+  /**
+   * The interface or class that this Normalizer supports.
+   *
+   * @var string
+   */
+  protected $supportedInterfaceOrClass = 'Drupal\Core\TypedData\PrimitiveInterface';
+
+  /**
+   * {@inheritdoc}
+   */
+  public function normalize($object, $format = NULL, array $context = array()) {
+    return $object->getCastedValue();
+  }
+
+}
diff --git a/core/modules/serialization/tests/src/Kernel/EntitySerializationTest.php b/core/modules/serialization/tests/src/Kernel/EntitySerializationTest.php
index 0f84d3d..a71af15 100644
--- a/core/modules/serialization/tests/src/Kernel/EntitySerializationTest.php
+++ b/core/modules/serialization/tests/src/Kernel/EntitySerializationTest.php
@@ -134,7 +134,7 @@ public function testNormalize() {
     $normalized = $this->serializer->normalize($this->entity);
 
     foreach (array_keys($expected) as $fieldName) {
-      $this->assertEqual($expected[$fieldName], $normalized[$fieldName], "ComplexDataNormalizer produces expected array for $fieldName.");
+      $this->assertSame($expected[$fieldName], $normalized[$fieldName], "Normalization produces expected array for $fieldName.");
     }
     $this->assertEqual(array_diff_key($normalized, $expected), array(), 'No unexpected data is added to the normalized array.');
   }
diff --git a/core/modules/serialization/tests/src/Unit/Normalizer/PrimitiveDataNormalizerTest.php b/core/modules/serialization/tests/src/Unit/Normalizer/PrimitiveDataNormalizerTest.php
new file mode 100644
index 0000000..be62aef
--- /dev/null
+++ b/core/modules/serialization/tests/src/Unit/Normalizer/PrimitiveDataNormalizerTest.php
@@ -0,0 +1,80 @@
+<?php
+
+namespace Drupal\Tests\serialization\Unit\Normalizer;
+
+use Drupal\Core\TypedData\DataDefinition;
+use Drupal\Core\TypedData\Plugin\DataType\BooleanData;
+use Drupal\Core\TypedData\Plugin\DataType\IntegerData;
+use Drupal\Core\TypedData\Plugin\DataType\StringData;
+use Drupal\Tests\UnitTestCase;
+use Drupal\serialization\Normalizer\PrimitiveDataNormalizer;
+
+/**
+ * @coversDefaultClass \Drupal\serialization\Normalizer\TypedDataNormalizer
+ * @group serialization
+ */
+class PrimitiveDataNormalizerTest extends UnitTestCase {
+
+  /**
+   * The TypedDataNormalizer instance.
+   *
+   * @var \Drupal\serialization\Normalizer\TypedDataNormalizer
+   */
+  protected $normalizer;
+
+  protected function setUp() {
+    $this->normalizer = new PrimitiveDataNormalizer();
+  }
+
+  /**
+   * @covers ::supportsNormalization
+   * @dataProvider dataProviderPrimitiveData
+   */
+  public function testSupportsNormalization($primitive_data, $value) {
+    $this->assertTrue($this->normalizer->supportsNormalization($primitive_data));
+  }
+
+  /**
+   * @covers ::supportsNormalization
+   */
+  public function testSupportsNormalizationFail() {
+    // Test that an object not implementing TypedDataInterface fails.
+    $this->assertFalse($this->normalizer->supportsNormalization(new \stdClass()));
+  }
+
+  /**
+   * @covers ::normalize
+   * @dataProvider dataProviderPrimitiveData
+   */
+  public function testNormalize($primitive_data, $value) {
+    $this->assertSame($value, $this->normalizer->normalize($primitive_data));
+  }
+
+  /**
+   * Data provider for testNormalize().
+   */
+  public function dataProviderPrimitiveData() {
+    $data = [];
+
+    $definition = DataDefinition::createFromDataType('string');
+    $string = new StringData($definition, 'string');
+    $string->setValue('test');
+
+    $data[] = [$string, 'test'];
+
+    $definition = DataDefinition::createFromDataType('integer');
+    $integer = new IntegerData($definition, 'integer');
+    $integer->setValue(5);
+
+    $data[] = [$integer, 5];
+
+    $definition = DataDefinition::createFromDataType('boolean');
+    $boolean = new BooleanData($definition, 'boolean');
+    $boolean->setValue(TRUE);
+
+    $data[] = [$boolean, TRUE];
+
+    return $data;
+  }
+
+}