diff --git a/requirements.txt b/requirements.txt
index 79823077..9836daef 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,6 +2,7 @@ Babel>=1.3
 Flask-Babel>=0.11.1
 Flask-Login>=0.3.2
 Flask-Principal>=0.3.2
+Flask-SimpleLDAP>=1.4.0
 singledispatch>=3.4.0.0
 backports_abc>=0.4
 Flask>=0.11