diff --git a/avatar/conf.py b/avatar/conf.py
index e25ee91..3c0fd07 100644
--- a/avatar/conf.py
+++ b/avatar/conf.py
@@ -8,6 +8,7 @@ class AvatarConf(AppConf):
     DEFAULT_SIZE = 80
     RESIZE_METHOD = Image.ANTIALIAS
     STORAGE_DIR = 'avatars'
+    GRAVATAR_FIELD = 'email'
     GRAVATAR_BASE_URL = 'http://www.gravatar.com/avatar/'
     GRAVATAR_BACKUP = True
     GRAVATAR_DEFAULT = None
diff --git a/avatar/templatetags/avatar_tags.py b/avatar/templatetags/avatar_tags.py
index 75a1a4f..6e2c6a5 100644
--- a/avatar/templatetags/avatar_tags.py
+++ b/avatar/templatetags/avatar_tags.py
@@ -31,8 +31,8 @@ def avatar_url(user, size=settings.AVATAR_DEFAULT_SIZE):
         params = {'s': str(size)}
         if settings.AVATAR_GRAVATAR_DEFAULT:
             params['d'] = settings.AVATAR_GRAVATAR_DEFAULT
-        path = "%s/?%s" % (hashlib.md5(force_bytes(user.email)).hexdigest(),
-                           urlencode(params))
+        path = "%s/?%s" % (hashlib.md5(force_bytes(
+            getattr(settings.GRAVATAR_FIELD))).hexdigest(), urlencode(params))
         return urljoin(settings.AVATAR_GRAVATAR_BASE_URL, path)
 
     return get_default_avatar_url()
diff --git a/docs/index.txt b/docs/index.txt
index c1dda78..4396d1c 100644
--- a/docs/index.txt
+++ b/docs/index.txt
@@ -117,6 +117,11 @@ AVATAR_DEFAULT_URL
     The default URL to default to if ``AVATAR_GRAVATAR_BACKUP`` is set to False
     and there is no ``Avatar`` instance found in the system for the given user.
 
+AVATAR_GRAVATAR_FIELD
+    The name of the user's field containing the gravatar email. Defaults to
+    ``email``. If you put, for example, ``gravatar``, django-avatar will get the
+    user's gravatar in ``user.gravatar``.
+
 Management Commands
 -------------------