diff --git a/requirements.txt b/requirements.txt
index 3e9aab1..111c2e4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,3 +4,6 @@ python-dateutil
 responses
 mock
 setuptools_scm
+MarkupSafe
+setuptools>=40.0
+configparser>=3.5
\ No newline at end of file
diff --git a/twitter_ads/client.py b/twitter_ads/client.py
index 6b91a5c..47b625d 100644
--- a/twitter_ads/client.py
+++ b/twitter_ads/client.py
@@ -29,6 +29,7 @@ def __init__(self,
         self._access_token = access_token
         self._access_token_secret = access_token_secret
         self._options = kwargs.get('options', {})
+        self._headers = kwargs.get('headers', {})
 
     def __repr__(self):
         return '<{name} object at {mem} consumer_key={key}>'.format(
@@ -42,6 +43,11 @@ def options(self):
         """Returns the options value."""
         return self._options
 
+    @property
+    def headers(self):
+        """Returns the headers value."""
+        return self._headers
+
     @property
     def consumer_key(self):
         """Returns the consumer_key value."""
diff --git a/twitter_ads/http.py b/twitter_ads/http.py
index 1931f12..c7e15b8 100644
--- a/twitter_ads/http.py
+++ b/twitter_ads/http.py
@@ -75,10 +75,12 @@ def __oauth_request(self):
         if 'headers' in self.options:
             headers.update(self.options['headers'].copy())
 
-        # internal-only
+        # DEPRECATED: internal-only (Should pass a header to the client)
         if 'x-as-user' in self._client.options:
             headers['x-as-user'] = self._client.options.get('x-as-user')
-
+        # Add headers from the client to the request (Client headers take priority)
+        for key, val in self._client.headers.items():
+            headers[key] = val
         params = self.options.get('params', None)
         data = self.options.get('body', None)
         files = self.options.get('files', None)