A surgical instrument has an end-effector located on the end of a rotatable shaft, the shaft projecting from a handle. A thumbwheel is provided at the proximal end of the handle, which controls the rotation of the shaft, and hence the rotational orientation of the end-effector. The end-effector is capable of grasping, cutting, and sealing and/or coagulating tissue, and one of the operations is controlled by a switch located on the upper surface of the proximal end of the handle. The switch is oriented on the handle to be generally above the thumbwheel, in a relative position to the thumbwheel so that both the thumbwheel and the switch may be activated by the user's thumb, without the user having to alter his grip on the handle. In one embodiment of the invention the switch is therefore vertically oriented above the thumbwheel.
