diff --git a/data/gui/default/window/simple_item_selector.cfg b/data/gui/default/window/simple_item_selector.cfg
index 4b69ccdc10d..74f9e80dd6e 100644
--- a/data/gui/default/window/simple_item_selector.cfg
+++ b/data/gui/default/window/simple_item_selector.cfg
@@ -129,7 +129,7 @@
 								[button]
 									id = "ok"
 									definition = "default"
-									label = "OK"
+									label = _ "OK"
 								[/button]
 
 							[/column]
@@ -142,7 +142,7 @@
 								[button]
 									id = "cancel"
 									definition = "default"
-									label = "Cancel"
+									label = _ "Cancel"
 								[/button]
 
 							[/column]