A monitoring device arranged to be fitted to a door, wherein the door includes an operating bar mounted on the door for angular movement about its axis and a handle which is connected to the operating bar by a pivotal connection; wherein the device comprises a body element and a cover element arranged to slide relative to the body element and the two elements having a closed configuration and an open configuration in which the cover element is extended relative to the body element thereby allowing the device to be fitted to a door; the body and cover elements being shaped so that when in the closed configuration a pocket is formed that substantially surrounds an operating bar and further wherein the cover element comprises a portion extending over a region of a handle of a door to which the device is fitted such that that handle is prevented from rotating relative to the door; and monitoring circuitry arranged to monitor the device.