A clinical review of patients treated by excision of the trapezium for carpometacarpal arthritis of the thumb is presented. Excision of the trapezium gave good results, particularly with respect to relief of pain. Hand function was good following excision of the trapezium, though there was some reduction in the power of opposition grip and pinch in three-quarters of the patients. This weakness may be due the the carpal instability that exists following the operative procedure.