An improved door locking and monitoring assembly is provided which is power activated. The assembly comprises a lock assembly in a housing, which housing is disposed in a door. The lock assembly has a latch trip member extending therefrom along with an ordinary latch. An actuating and switching assembly is disposed in a housing located in the door frame, including a power activated bolt located opposite from and adapted to displace the trip member, and a switch located opposite the latch and adapted to signal the relative position of the latch. The lock assembly has a series of inter-acting, pivoted arms which co-act in a manner to prevent rotation of the door-knob hub while locking the latch in an extended position, all upon actuation of the bolt to displace the trip member into the lock assembly. Signalling means are employed to indicate the state of the lock assembly.