diff --git a/doc/en_US/requirements.markdown b/doc/en_US/requirements.markdown
index cbc2187c0..7c3485801 100644
--- a/doc/en_US/requirements.markdown
+++ b/doc/en_US/requirements.markdown
@@ -48,6 +48,8 @@ Do not use Sqlite on NFS mounts, only when you have a disk with fast I/O.
 
 Kanboard is pre-configured to work with Apache (URL rewriting).
 
+Note: Kanboard is not compatible with Apache `mod_security`.
+
 ### PHP Versions
 
 | PHP Version    |