diff --git a/src/Datastore/Connection/Rest.php b/src/Datastore/Connection/Rest.php
index ae0261f28b66..6ae775532610 100644
--- a/src/Datastore/Connection/Rest.php
+++ b/src/Datastore/Connection/Rest.php
@@ -38,10 +38,14 @@ class Rest implements ConnectionInterface
      */
     public function __construct(array $config = [])
     {
+        $emulatorHost = getenv('DATASTORE_EMULATOR_HOST');
+
+        $baseUri = $this->getEmulatorBaseUri(self::BASE_URI, $emulatorHost);
+
         $this->setRequestWrapper(new RequestWrapper($config));
         $this->setRequestBuilder(new RequestBuilder(
             __DIR__ . '/ServiceDefinition/datastore-v1.json',
-            self::BASE_URI
+            $baseUri
         ));
     }
 
diff --git a/src/Datastore/DatastoreClient.php b/src/Datastore/DatastoreClient.php
index eeae33e17e58..55d98628bd8e 100644
--- a/src/Datastore/DatastoreClient.php
+++ b/src/Datastore/DatastoreClient.php
@@ -35,6 +35,12 @@
  * through use of data partitions. A partition ID can be supplied when creating an instance of Cloud Datastore, and will
  * be used in all operations executed in that instance.
  *
+ * To enable the
+ * [Google Cloud Datastore Emulator](https://cloud.google.com/datastore/docs/tools/datastore-emulator),
+ * set the
+ * [`PUBSUB_EMULATOR_HOST`](https://cloud.google.com/datastore/docs/tools/datastore-emulator#setting_environment_variables)
+ * environment variable.
+ *
  * Example:
  * ```
  * use Google\Cloud\ServiceBuilder;
@@ -62,6 +68,18 @@
  *     'namespaceId' => 'my-application-namespace'
  * ]);
  * ```
+ *
+ * ```
+ * // Using the Datastore Emulator
+ * use Google\Cloud\ServiceBuilder;
+ *
+ * // Be sure to use the port specified when starting the emulator.
+ * // `8900` is used as an example only.
+ * putenv('DATASTORE_EMULATOR_HOST=http://localhost:8900');
+ *
+ * $cloud = new ServiceBuilder();
+ * $datastore = $cloud->datastore();
+ * ```
  */
 class DatastoreClient
 {
diff --git a/src/PubSub/PubSubClient.php b/src/PubSub/PubSubClient.php
index bd22bf1514c6..69df97e58bf1 100644
--- a/src/PubSub/PubSubClient.php
+++ b/src/PubSub/PubSubClient.php
@@ -26,8 +26,9 @@
  * messages between independent applications. Find more information at
  * [Google Cloud Pub/Sub docs](https://cloud.google.com/pubsub/docs/).
  *
- * The [PUBSUB_EMULATOR_HOST](https://cloud.google.com/pubsub/emulator#env) environment variable
- * from the gcloud SDK is honored, otherwise the actual API endpoint will be used.
+ * To enable the [Google Cloud Pub/Sub Emulator](https://cloud.google.com/pubsub/emulator),
+ * set the [`PUBSUB_EMULATOR_HOST`](https://cloud.google.com/pubsub/emulator#env)
+ * environment variable.
  *
  * Example:
  * ```
@@ -44,6 +45,18 @@
  *
  * $pubsub = new PubSubClient();
  * ```
+ *
+ * ```
+ * // Using the Pub/Sub Emulator
+ * use Google\Cloud\ServiceBuilder;
+ *
+ * // Be sure to use the port specified when starting the emulator.
+ * // `8900` is used as an example only.
+ * putenv('PUBSUB_EMULATOR_HOST=http://localhost:8900');
+ *
+ * $cloud = new ServiceBuilder();
+ * $pubsub = $cloud->pubsub();
+ * ```
  */
 class PubSubClient
 {