diff --git a/Help/command/set_tests_properties.rst b/Help/command/set_tests_properties.rst
index 8eac0e2a99..a21f746e96 100644
--- a/Help/command/set_tests_properties.rst
+++ b/Help/command/set_tests_properties.rst
@@ -6,6 +6,7 @@ Set a property of the tests.
 .. code-block:: cmake
 
   set_tests_properties(<tests>...
+                       [DIRECTORY <dir>]
                        PROPERTIES <prop1> <value1>
                        [<prop2> <value2>]...)