diff --git a/basics/routing.md b/basics/routing.md
index a417c23..2897e25 100644
--- a/basics/routing.md
+++ b/basics/routing.md
@@ -162,4 +162,8 @@ $router->route(
 	'APP_NAME',
 	ORG_ID, ACCOUNT
 );
-```
\ No newline at end of file
+```
+
+## Notes
+
+* 2-character routes on the first level are discouraged because they may conflict with ISO 639-1 codes (e.g. /hr/staff/list)
\ No newline at end of file