diff --git a/src/MailChimp.php b/src/MailChimp.php
index f30a76a..b310808 100644
--- a/src/MailChimp.php
+++ b/src/MailChimp.php
@@ -220,7 +220,8 @@ private function makeRequest($http_verb, $method, $args = array(), $timeout = se
         $httpHeader = array(
             'Accept: application/vnd.api+json',
             'Content-Type: application/vnd.api+json',
-            'Authorization: apikey ' . $this->api_key
+            'Authorization: apikey ' . $this->api_key,
+            'Expect:'
         );
 
         if (isset($args["language"])) {