diff --git a/src/main/java/com/bandwidth/sdk/model/bxml/StartStream.java b/src/main/java/com/bandwidth/sdk/model/bxml/StartStream.java
index 491512e9..2cf1feb1 100644
--- a/src/main/java/com/bandwidth/sdk/model/bxml/StartStream.java
+++ b/src/main/java/com/bandwidth/sdk/model/bxml/StartStream.java
@@ -33,17 +33,43 @@
 @EqualsAndHashCode
 /**
  *
- * @param name (str, optional): A name to refer to this stream by. Used when sending <StopStream>. If not provided, it will default to the generated stream id as sent in the Media Stream Started webhook.
- * @param tracks (str, optional): The part of the call to send a stream from. inbound, outbound or both. Default is inbound.
- * @param destination (str, optional): A websocket URI to send the stream to. The audio from the specified tracks will be sent via websocket to this URL as base64-encoded PCMU/G711 audio. See below for more details on the websocket packet format.
- * @param streamEventUrl (str, optional): URL to send the associated Webhook events to during this stream's lifetime. Does not accept BXML. May be a relative URL.
- * @param streamEventMethod (str, optional): The HTTP method to use for the request to streamEventUrl. GET or POST. Default value is POST.
- * @param username (str, optional): The username to send in the HTTP request to streamEventUrl. If specified, the URLs must be TLS-encrypted (i.e., https).
- * @param password (str, optional): The password to send in the HTTP request to streamEventUrl. If specified, the URLs must be TLS-encrypted (i.e., https).
+ * @param name              (str, optional): A name to refer to this stream by.
+ *                          Used when sending <StopStream>. If not provided, it
+ *                          will default to the generated stream id as sent in
+ *                          the Media Stream Started webhook.
+ * @param mode              (str, optional): The mode to use for the stream.
+ *                          unidirectional or bidirectional. Specifies whether
+ *                          the audio being streamed over the WebSocket is
+ *                          bidirectional (the service can both read and write
+ *                          audio over the WebSocket) or unidirectional
+ *                          (one-way, read-only). Default is unidirectional.
+ * @param tracks            (str, optional): The part of the call to send a
+ *                          stream from. inbound, outbound or both. Default is
+ *                          inbound.
+ * @param destination       (str, optional): A websocket URI to send the stream
+ *                          to. The audio from the specified tracks will be sent
+ *                          via websocket to this URL as base64-encoded
+ *                          PCMU/G711 audio. See below for more details on the
+ *                          websocket packet format.
+ * @param streamEventUrl    (str, optional): URL to send the associated Webhook
+ *                          events to during this stream's lifetime. Does not
+ *                          accept BXML. May be a relative URL.
+ * @param streamEventMethod (str, optional): The HTTP method to use for the
+ *                          request to streamEventUrl. GET or POST. Default
+ *                          value is POST.
+ * @param username          (str, optional): The username to send in the HTTP
+ *                          request to streamEventUrl. If specified, the URLs
+ *                          must be TLS-encrypted (i.e., https).
+ * @param password          (str, optional): The password to send in the HTTP
+ *                          request to streamEventUrl. If specified, the URLs
+ *                          must be TLS-encrypted (i.e., https).
  *
- *        Nested Verbs:
- *        @param  StreamParam: (optional) You may specify up to 12 <StreamParam/> elements nested within a <StartStream> tag.
- *          These elements define optional user specified parameters that will be sent to the destination URL when the stream is first started.
+ *                          Nested Verbs:
+ * @param StreamParam:      (optional) You may specify up to 12 <StreamParam/>
+ *                          elements nested within a <StartStream> tag.
+ *                          These elements define optional user specified
+ *                          parameters that will be sent to the destination URL
+ *                          when the stream is first started.
  *
  */
 public class StartStream implements Verb {
@@ -53,6 +79,9 @@ public class StartStream implements Verb {
     @XmlAttribute
     protected String name;
 
+    @XmlAttribute
+    protected String mode;
+
     @XmlAttribute
     @Default
     protected CallDirectionEnum tracks = CallDirectionEnum.INBOUND;
diff --git a/src/test/java/com/bandwidth/sdk/unit/models/bxml/StartStreamVerbTest.java b/src/test/java/com/bandwidth/sdk/unit/models/bxml/StartStreamVerbTest.java
index 18b6134f..5fbde02f 100644
--- a/src/test/java/com/bandwidth/sdk/unit/models/bxml/StartStreamVerbTest.java
+++ b/src/test/java/com/bandwidth/sdk/unit/models/bxml/StartStreamVerbTest.java
@@ -37,6 +37,7 @@ public class StartStreamVerbTest {
                         .build();
         StartStream startStream = StartStream.builder()
                         .name("stream1")
+                        .mode("unidirectional")
                         .tracks(CallDirectionEnum.INBOUND)
                         .destination("testurl.com")
                         .streamEventUrl("eventurl.com")
@@ -49,7 +50,7 @@ public class StartStreamVerbTest {
         @Test
         public void startStreamVerbWorks() throws JAXBException {
                 JAXBContext jaxbContext = JAXBContext.newInstance(Bxml.class);
-                String expectedBxml = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?><Bxml><StartStream name=\"stream1\" tracks=\"INBOUND\" destination=\"testurl.com\" streamEventUrl=\"eventurl.com\" streamEventMethod=\"POST\" username=\"user\" password=\"pass\"><StreamParam name=\"name1\" value=\"value1\"/><StreamParam name=\"name2\" value=\"value2\"/></StartStream></Bxml>";
+                String expectedBxml = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?><Bxml><StartStream name=\"stream1\" mode=\"unidirectional\" tracks=\"INBOUND\" destination=\"testurl.com\" streamEventUrl=\"eventurl.com\" streamEventMethod=\"POST\" username=\"user\" password=\"pass\"><StreamParam name=\"name1\" value=\"value1\"/><StreamParam name=\"name2\" value=\"value2\"/></StartStream></Bxml>";
 
                 assertThat(new Bxml().with(startStream).toBxml(jaxbContext), is(expectedBxml));
         }