diff --git a/doc/source/launcher.rst b/doc/source/launcher.rst
index 09516a4..e64aa49 100644
--- a/doc/source/launcher.rst
+++ b/doc/source/launcher.rst
@@ -14,4 +14,6 @@ them with additional ``-a`` switches.
 
 The Trollflow2 process can be terminated gracefully by sending SIGTERM
 to the it, eg. by ``kill -SIGTERM <pid>`` where ``<pid>`` is the
-process ID number of Trollflow2.
+process ID number of Trollflow2.  After this no new messages will be
+accepted, and the completion of currently running processing will exit
+Trollflow2.