diff --git a/requirements.txt b/requirements.txt
index 47fa8ac..fdff77b 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,3 @@
-bottle>=0.12.8
-ldap3>=0.9
+bottle >= 0.12.8
+ldap3 >= 0.9, < 2.0
 configparser; python_version < '3.3'