diff --git a/twython/twython.py b/twython/twython.py
index 14b5806..329bfae 100644
--- a/twython/twython.py
+++ b/twython/twython.py
@@ -93,6 +93,18 @@ class APILimit(TwythonError):
     def __str__(self):
         return repr(self.msg)
 
+class RateLimitError(TwythonError):
+    """
+        Raised when you've hit a rate limit.  retry_wait_seconds is the number of seconds to
+        wait before trying again.
+    """
+    def __init__(self, msg, retry_wait_seconds):
+        self.msg = msg
+        self.retry_wait_seconds = int(retry_wait_seconds)
+
+    def __str__(self):
+        return repr(self.msg)
+
 
 class AuthError(TwythonError):
     """
@@ -308,6 +320,11 @@ class Twython(object):
         searchURL = Twython.constructApiURL("http://search.twitter.com/search.json", kwargs)
         try:
             resp, content = self.client.request(searchURL, "GET", headers = self.headers)
+
+            if resp.status == 420:
+                retry_wait_seconds = resp['retry-after']
+                raise RateLimitError("getSearchTimeline() is being rate limited.  Retry after %s seconds." % retry_wait_seconds, retry_wait_seconds)
+
             return simplejson.loads(content.decode('utf-8'))
         except HTTPError, e:
             raise TwythonError("getSearchTimeline() failed with a %s error code." % `e.code`, e.code)