diff --git a/tests/unit/twiml/__init__.py b/tests/unit/twiml/__init__.py
index 65873e0927..1bc5a944df 100644
--- a/tests/unit/twiml/__init__.py
+++ b/tests/unit/twiml/__init__.py
@@ -3,7 +3,7 @@
 from nose.tools import raises
 from six import text_type
 
-from twilio.twiml import TwiMLException, TwiML
+from twilio.twiml import format_language, TwiMLException, TwiML
 
 
 class TwilioTest(unittest.TestCase):
@@ -14,3 +14,19 @@ def strip(self, xml):
     def test_append_fail(self):
         t = TwiML()
         t.append('foobar')
+
+    def test_format_language_none(self):
+        language = None
+        self.assertEqual(language, format_language(language))
+
+    def test_format_language_valid(self):
+        language = 'en-US'
+        self.assertEqual(language, format_language(language))
+
+    def test_format_language_coerced(self):
+        language = 'EN_us'
+        self.assertEqual('en-US', format_language(language))
+
+    @raises(TwiMLException)
+    def test_format_language_fail(self):
+        format_language('this is invalid')
diff --git a/twilio/twiml/__init__.py b/twilio/twiml/__init__.py
index 6c7c05a94c..8e17325c7f 100644
--- a/twilio/twiml/__init__.py
+++ b/twilio/twiml/__init__.py
@@ -1,3 +1,4 @@
+import re
 import xml.etree.ElementTree as ET
 
 
@@ -9,6 +10,21 @@ def lower_camel(string):
     return result[0].lower() + result[1:]
 
 
+def format_language(language):
+    """
+    Attempt to format language parameter as 'ww-WW'.
+
+    :param string language: language parameter
+    """
+    if not language:
+        return language
+
+    if not re.match('^[a-zA-Z]{2}[_-][a-zA-Z]{2}$', language):
+        raise TwiMLException('Invalid value for language parameter.')
+
+    return language[0:2].lower() + '-' + language[3:5].upper()
+
+
 class TwiMLException(Exception):
     pass
 
diff --git a/twilio/twiml/voice_response.py b/twilio/twiml/voice_response.py
index 59d2593aef..c6151c8121 100644
--- a/twilio/twiml/voice_response.py
+++ b/twilio/twiml/voice_response.py
@@ -1,7 +1,7 @@
 import json
 from six import string_types
 
-from twilio.twiml import TwiML
+from twilio.twiml import TwiML, format_language
 
 
 class VoiceResponse(TwiML):
@@ -111,6 +111,7 @@ def gather(self,
                hints=None,
                barge_in=None,
                acknowledge_sound_url=None,
+               input=None,
                **kwargs):
         """
         Add a new <Gather> element
@@ -126,6 +127,7 @@ def gather(self,
         :param hints: speech recognition hints
         :param barge_in: stop playing media upon speech
         :param acknowledge_sound_url: url to hit when sound starts
+        :param input: type Twilio should accept "dtfm", "speech", "dtfm speech"
         :param kwargs: additional attributes
         :return: <Gather> element
         """
@@ -135,6 +137,13 @@ def gather(self,
             timeout=timeout,
             finish_on_key=finish_on_key,
             num_digits=num_digits,
+            partial_result_callback=partial_result_callback,
+            partial_result_callback_method=partial_result_callback_method,
+            language=format_language(language),
+            hints=hints,
+            barge_in=barge_in,
+            acknowledge_sound_url=acknowledge_sound_url,
+            input=input,
             **kwargs
         ))