Abstract: An electronically activated safety mechanism for a firearm which introduces a simple obstruction to the firing-pin itself, thereby offering a high degree of simplicity and reliability. In a preferred embodiment, a solid cylindrical block is provided and is movable along a first axis between a first, safety position and a second, firing position through the action of a first solenoid. The firing-pin block includes a bore formed centrally therethrough which is in alignment with the firing-pin when the cylindrical block is in a second, firing position. Electronics entirely self-contained within the weapon may be used for both arming and disarming, with such capabilities taking the form of a voice-response unit, keypad with security code or other operator-specific configurations. In an alternative embodiment of this aspect of the invention, an off-weapon signaling unit is provided, for example, in the form of a watch, bracelet, or other item worn by an authorized user.