diff --git a/github3/pulls.py b/github3/pulls.py
index 471961e27..6a40753d7 100644
--- a/github3/pulls.py
+++ b/github3/pulls.py
@@ -303,18 +303,18 @@ def issue_comments(self, number=-1, etag=None):
         return self._iter(int(number), url, IssueComment, etag=etag)
 
     @requires_auth
-    def merge(self, commit_message=None, sha=None, squash=False):
+    def merge(self, commit_message=None, sha=None, merge_method="merge"):
         """Merge this pull request.
 
         :param str commit_message: (optional), message to be used for the
             merge commit
         :param str sha: (optional), SHA that pull request head must match
             to merge.
-        :param bool squash: (optional), commit a single commit to the
-            head branch.
+        :param str merge_method: (optional), Change the merge method.
+            Either 'merge', 'squash' or 'rebase'. Default is 'merge'.
         :returns: bool
         """
-        parameters = {'squash': squash}
+        parameters = {'merge_method': merge_method}
         if sha:
             parameters['sha'] = sha
         if commit_message is not None:
diff --git a/tests/unit/test_pulls.py b/tests/unit/test_pulls.py
index 0b68ee4c0..4fc31f250 100644
--- a/tests/unit/test_pulls.py
+++ b/tests/unit/test_pulls.py
@@ -99,16 +99,16 @@ def test_merge(self):
 
         self.put_called_with(
             url_for('merge'),
-            data={"squash": False}
+            data={"merge_method": "merge"}
         )
 
     def test_merge_squash_message(self):
         """Show that a user can merge a Pull Request."""
-        self.instance.merge('commit message', squash=True)
+        self.instance.merge('commit message', merge_method='squash')
 
         self.put_called_with(
             url_for('merge'),
-            data={"squash": True, "commit_message": "commit message"}
+            data={"merge_method": "squash", "commit_message": "commit message"}
         )
 
     def test_patch(self):