Abstract: An ultrasonic clamp coagulator assembly that is configured to permit selective cutting, coagulation, and fine dissection required in fine and delicate surgical procedures. The assembly includes a clamping mechanism, including a clamp arm cam-mounted at the distal portion of the instrument, which is specifically configured to create a desired level of tissue clamping forces. The balanced blade provides a functional asymmetry for improved visibility at the blade tip and a multitude of edges and surfaces, designed to provide a multitude of tissue effects: clamped coagulation, clamped cutting, grasping, back-cutting, dissection, spot coagulation, tip penetration and tip scoring. The assembly also features hand activation configured to provide an ergonomical grip and operation for the surgeon. Hand switches are placed in the range of the natural axial motion of the user's index or middle fingers, whether gripping the surgical instrument right-handed or left handed.