diff --git a/services.md b/services.md
index befe1806f7441247cc48f6112d75b353738a7ab7..c14a110daf80a332099d1099d88be36d46c93baf 100644
--- a/services.md
+++ b/services.md
@@ -205,6 +205,7 @@ Office
 * [GNUKhata - Fast Feature rich Free accounting software](http://gnukhata.in/).
 * [draw.io](https://github.com/jgraph/drawio).
 * [helpy](https://github.com/helpyio/helpy/): helpdesk customer support application.
+* [Zammad](https://zammad.org/): web-based, open source user support/ticketing solution.
 * [Discourse](https://www.discourse.org/): "civilized discussion for your community".
 
 Finance: