Abstract: A locking mechanism for sliding doors and windows includes a lock with a lock cylinder having a key hole for the key. The lock includes a tab and a cylinder pin. The locking mechanism further includes a toggle box, a track, a stopper, a chamber and an operating latch, a blocking toggle, an operating handle and left and right side faces. The key includes a key shaft, key head, a bore, an inlet and key teeth. The abutment of the cylinder pin on the stopper promotes the blocking in the locking mechanism which presents reduced dimensions for application in modern design frame structures.