diff --git a/strmangle_test.go b/strmangle_test.go
index b575b23..f61d55f 100644
--- a/strmangle_test.go
+++ b/strmangle_test.go
@@ -197,6 +197,7 @@ func TestTitleCase(t *testing.T) {
 		{"ssn", "SSN"},
 		{"tz", "TZ"},
 		{"thing_guid", "ThingGUID"},
+		{"thing_guids", "ThingGuids"},
 		{"guid_thing", "GUIDThing"},
 		{"thing_guid_thing", "ThingGUIDThing"},
 		{"id", "ID"},