Abstract: The present invention relates to an arrangement for a lock (2) for doors (3). An electromechanical unit (6), with an integral electrically driven stepping motor (7), which is intended to operate the lock handle by actuation of the motor (7), is capable of being applied to the inside (3A) of the door (3). An electronic unit, which is capable of being actuated by an electronic key, is capable of being mounted on the outside of the door (3), which unit is so arranged as to interact with a magnetic field with a predetermined frequency and by wireless communication between the key and the unit. A power supply unit is provided, and a central processor unit is so arranged as to monitor the aforementioned electromechanical unit (6) and an RFID reader contained in the electronic unit. Arranged between the motor (7) and the lock (2) is a rotating driver (13) for transferring the force from the motor (7) to the lock (2).