The invention relates to a lock for a motor vehicle door with: a locking mechanism; an actuating compound lever (1, 2) which acts upon the locking mechanism; and a drive unit (3, 4) for at least one lever (2) of the actuating compound lever (1, 2). The drive unit (3, 4) comprises at least one motor (3) and a bolt (4) which is acted upon by the motor (3) and is provided with a recess (8) for at least one output shaft (5) of the motor (3).