Abstract: A latch assembly is for a lock of a door and includes a latch movably disposed within the door. A sensor is configured to sense when the latch is generally located at a particular position with respect to the door. Preferably, the latch is displaceable between an extended position, at which the latch is engageable with a strike, and a retracted position at which the door is moveable with respect to a frame, and the sensor preferably senses when the latch is located at at least one of these two positions. The sensor preferably includes a reed switch and a magnet, and preferably generates a signal when the latch is located at, or displaces from, the particular position. Further, the sensor is coupleable with either a processing device, such as a computer or controller, or an alarm device, such as a horn, a light or a speaker.