Abstract: An ergonomically-shaped hand controller of the type commonly referred to as a "mouse", is specially configured to prevent or reduce hand muscle fatigue despite continuous use over a protracted period of time. A housing for receiving the anterior surface of the hand comprises an arched metacarpalphalangeal support surface, distal phalange support surfaces for the volar pads of the thumb and forefinger and a medial ledge for supporting the remaining three ulnar fingers in a partially wrapped configuration with flexion of the distal, middle and proximal phalanges.