A folding knife that uses a four bar linkage mechanism to open and close. The knife can include a means of one hand opening and closing as well as a means to become latched in, and released from, a fixed position. The four bar linkage knife includes a blade, a handle, and the motion of a four bar linkage to open and close the knife. The four bar knife provides inherent safety because the four bar linkage motion can not fold onto the users hand.