diff --git a/authens/conf.py b/authens/conf.py
index 732b984..46867b8 100644
--- a/authens/conf.py
+++ b/authens/conf.py
@@ -1,4 +1,5 @@
 LDAP_SERVER_URL = "ldaps://ldap.spi.ens.fr:636"
 AUTHENS_USE_OLDCAS = True
 AUTHENS_USE_PASSWORD = True
+USE_LDAP = True
 # TODO: CAS_SERVER_URL
diff --git a/authens/shortcuts.py b/authens/shortcuts.py
index 2bed72b..cd544ba 100644
--- a/authens/shortcuts.py
+++ b/authens/shortcuts.py
@@ -1,7 +1,10 @@
 """Helper functions to get CAS metadata and create CAS accounts."""
 
+import warnings
+
 # TODO: make the python-ldap dependency optional
 import ldap
+
 from django.conf import settings
 from django.contrib.auth import get_user_model
 
@@ -24,6 +27,10 @@ def fetch_cas_account(cas_login):
     if not cas_login.isalnum():
         raise ValueError("Illegal CAS login: {}".format(cas_login))
 
+    if not getattr(settings, "USE_LDAP", default_conf.USE_LDAP):
+        warnings.warn("Use of LDAP is disabled", RuntimeWarning)
+        return None
+
     ldap_url = getattr(settings, "LDAP_SERVER_URL", default_conf.LDAP_SERVER_URL)
     ldap_obj = ldap.initialize(ldap_url)
     res = ldap_obj.search_s(