diff --git a/CHANGES b/CHANGES
index 5ea2baae..5df663ea 100644
--- a/CHANGES
+++ b/CHANGES
@@ -51,6 +51,9 @@ Version 1.0
   loading.
 - Ported testsuite to py.test.
 - Deprecated ``request.json`` in favour of ``request.get_json()``.
+- Add "pretty" and "compressed" separators definitions in jsonify() method.
+  Reduces JSON response size when JSONIFY_PRETTYPRINT_REGULAR=False by removing
+  unnecessary white space included by default after separators.
 
 
 Version 0.10.2
diff --git a/flask/json.py b/flask/json.py
index a0ed7041..318fe28b 100644
--- a/flask/json.py
+++ b/flask/json.py
@@ -227,15 +227,22 @@ def jsonify(*args, **kwargs):
     This function's response will be pretty printed if it was not requested
     with ``X-Requested-With: XMLHttpRequest`` to simplify debugging unless
     the ``JSONIFY_PRETTYPRINT_REGULAR`` config parameter is set to false.
+    Compressed (not pretty) formatting currently means no indents and no
+    spaces after separators.
 
     .. versionadded:: 0.2
     """
+
     indent = None
+    separators = (',', ':')
+
     if current_app.config['JSONIFY_PRETTYPRINT_REGULAR'] \
        and not request.is_xhr:
         indent = 2
+        separators = (', ', ': ')
+
     return current_app.response_class(dumps(dict(*args, **kwargs),
-        indent=indent),
+        indent=indent, separators=separators),
         mimetype='application/json')
 
 
diff --git a/tests/test_basic.py b/tests/test_basic.py
index 55fd155a..2f024a5d 100644
--- a/tests/test_basic.py
+++ b/tests/test_basic.py
@@ -959,6 +959,36 @@ def test_make_response_with_response_instance():
         assert rv.headers['X-Foo'] == 'bar'
 
 
+def test_jsonify_no_prettyprint():
+    app = flask.Flask(__name__)
+    app.config.update({"JSONIFY_PRETTYPRINT_REGULAR": False})
+    with app.test_request_context():
+        compressed_msg = b'{"msg":{"submsg":"W00t"},"msg2":"foobar"}'
+        uncompressed_msg = {
+            "msg": {
+                "submsg": "W00t"
+            },
+            "msg2": "foobar"
+            }
+
+        rv = flask.make_response(
+            flask.jsonify(uncompressed_msg), 200)
+        assert rv.data == compressed_msg
+
+
+def test_jsonify_prettyprint():
+    app = flask.Flask(__name__)
+    app.config.update({"JSONIFY_PRETTYPRINT_REGULAR": True})
+    with app.test_request_context():
+        compressed_msg = {"msg":{"submsg":"W00t"},"msg2":"foobar"}
+        pretty_response =\
+            b'{\n  "msg": {\n    "submsg": "W00t"\n  }, \n  "msg2": "foobar"\n}'
+
+        rv = flask.make_response(
+            flask.jsonify(compressed_msg), 200)
+        assert rv.data == pretty_response
+
+
 def test_url_generation():
     app = flask.Flask(__name__)