Little is yet known about function, disease, and the efficacy of surgery in the rheumatoid hand. Subjective assessment methods have been reviewed but found to lack definition and precision and are difficult to quantify. The concept of the objective assessment of hand function at the digital level is emphasised and the value of cybernometer* measurements before and after corrective hand surgery is clearly demonstrated. Only by measuring the forces of the individual digits can the function of the hand be shown to improve in a quantitative fashion to the greater benefit of both patient and surgeon.