Abstract: A lever-type electrical connector assembly is provided that includes first and second electrical connectors having an actuating lever movably mounted thereon for movement between a release position with the connectors un-mated and a lock position with the connectors mated. In one form, a blocking member is provided between the first connector and the actuating lever for holding the actuating lever in the release position. A second connector includes a release member for shifting the blocking member to allow the actuating lever to move from the release position to the lock position. In another form, the electrical connector assembly is configured to precisely maximize the mechanical advantage provided by the actuating lever by including a predetermined force transmitting engagement portion at which the lever actuator engages one of the connectors to transmit a concentrated, predetermined leveraged output force thereto upon pivoting of the lever from the release to the lock position.