An interchangeable electro-mechanical lock core for use with a lock device having a locked state and an unlocked state, the lock device including an opening sized to receive the interchangeable lock core , the interchangeable lock core comprising: a lock core body having a front end and a rear end; a moveable plug positioned within an interior of the lock core body proximate a rear end of the lock core body , the moveable plug having a first position relative to the lock core body which corresponds to the lock device being in a locked state and a second position relative to the lock core body which corresponds to the lock device being in the unlocked state, the moveable plug being rotatable between the first position and the second position about a moveable plug axis ; a core keeper , the core keeper being positionable in a retain position wherein the core keeper extends beyond the envelope of the lock core body to hold the lock core body in the opening of the lock device and a remove position wherein the core keeper is retracted towards the lock core body relative to the retain position; an operator actuatable assembly supported by the lock core body and including an operator actuatable input device positioned forward of the front end of the lock core body ; an electro-mechanical control system which in a first configuration operatively couples the operator actuatable input device of the operator actuatable assembly to the moveable plug and in a second configuration uncouples the operator actuatable input device of the operator actuatable assembly from the moveable plug ; characterized in that the core keeper is moveably coupled to the lock core body and by an actuator accessible from an exterior of the lock core body , the actuator operatively coupled to the core keeper independent of the moveable plug to move the core keeper from the retain position to the remove position. a lock core body having a front end and a rear end; a moveable plug positioned within an interior of the lock core body proximate a rear end of the lock core body , the moveable plug having a first position relative to the lock core body which corresponds to the lock device being in a locked state and a second position relative to the lock core body which corresponds to the lock device being in the unlocked state, the moveable plug being rotatable between the first position and the second position about a moveable plug axis ; a core keeper , the core keeper being positionable in a retain position wherein the core keeper extends beyond the envelope of the lock core body to hold the lock core body in the opening of the lock device and a remove position wherein the core keeper is retracted towards the lock core body relative to the retain position; an operator actuatable assembly supported by the lock core body and including an operator actuatable input device positioned forward of the front end of the lock core body ; an electro-mechanical control system which in a first configuration operatively couples the operator actuatable input device of the operator actuatable assembly to the moveable plug and in a second configuration uncouples the operator actuatable input device of the operator actuatable assembly from the moveable plug ; characterized in that the core keeper is moveably coupled to the lock core body and by an actuator accessible from an exterior of the lock core body , the actuator operatively coupled to the core keeper independent of the moveable plug to move the core keeper from the retain position to the remove position. <EOS>