diff --git a/flask/__init__.py b/flask/__init__.py
index 196eb03302..ac1a3a0000 100644
--- a/flask/__init__.py
+++ b/flask/__init__.py
@@ -20,7 +20,7 @@
 
 from .app import Flask, Request, Response
 from .config import Config
-from .helpers import url_for, jsonify, json_available, flash, \
+from .helpers import url_for, jsonify, flash, \
     send_file, send_from_directory, get_flashed_messages, \
     get_template_attribute, make_response, safe_join, \
     stream_with_context
@@ -37,8 +37,8 @@
      request_finished, got_request_exception, request_tearing_down
 
 # only import json if it's available
-if json_available:
-    from .helpers import json
+from .helpers import json
 
 # backwards compat, goes away in 1.0
 from .sessions import SecureCookieSession as Session
+json_available = True
diff --git a/flask/helpers.py b/flask/helpers.py
index 7e20c97d47..b2d34a71df 100644
--- a/flask/helpers.py
+++ b/flask/helpers.py
@@ -23,21 +23,9 @@
 from werkzeug.urls import url_quote
 from functools import update_wrapper
 
-# try to load the best simplejson implementation available.  If JSON
-# is not installed, we add a failing class.
-json_available = True
-json = None
-try:
-    import simplejson as json
-except ImportError:
-    try:
-        import json
-    except ImportError:
-        try:
-            # Google Appengine offers simplejson via django
-            from django.utils import simplejson as json
-        except ImportError:
-            json_available = False
+# Use the same json implementation as itsdangerous on which we
+# depend anyways.
+from itsdangerous import simplejson as json
 
 
 from werkzeug.datastructures import Headers
@@ -55,19 +43,10 @@
      current_app, request
 
 
-def _assert_have_json():
-    """Helper function that fails if JSON is unavailable."""
-    if not json_available:
-        raise RuntimeError('simplejson not installed')
-
-
 # figure out if simplejson escapes slashes.  This behavior was changed
 # from one version to another without reason.
-if not json_available or '\\/' not in json.dumps('/'):
-
+if '\\/' not in json.dumps('/'):
     def _tojson_filter(*args, **kwargs):
-        if __debug__:
-            _assert_have_json()
         return json.dumps(*args, **kwargs).replace('/', '\\/')
 else:
     _tojson_filter = json.dumps
@@ -192,8 +171,6 @@ def get_current_user():
 
     .. versionadded:: 0.2
     """
-    if __debug__:
-        _assert_have_json()
     return current_app.response_class(json.dumps(dict(*args, **kwargs),
         indent=None if request.is_xhr else 2), mimetype='application/json')
 
diff --git a/flask/wrappers.py b/flask/wrappers.py
index 3ee718ffb8..060ee25b51 100644
--- a/flask/wrappers.py
+++ b/flask/wrappers.py
@@ -14,7 +14,7 @@
 
 from .exceptions import JSONBadRequest
 from .debughelpers import attach_enctype_error_multidict
-from .helpers import json, _assert_have_json
+from .helpers import json
 from .globals import _request_ctx_stack
 
 
@@ -95,8 +95,6 @@ def json(self):
 
         This requires Python 2.6 or an installed version of simplejson.
         """
-        if __debug__:
-            _assert_have_json()
         if self.mimetype == 'application/json':
             request_charset = self.mimetype_params.get('charset')
             try: