The effect of occupational therapy for patients awaiting surgery for isolated osteoarthritis of the carpometacarpal joint of the thumb was assessed. Thirty-three patients awaiting joint replacement because of pain were randomised into three groups. One group was treated with technical accessories, two other groups had in addition one of two types of splints, and all patients received extensive advice on how to accommodate activities of daily living. They all had an initial seven months' trial on this regimen at which time 23/33 (70%) no longer required an operation. During the following seven years four patients died, but only two of the remaining 19 patients wanted an operation. We therefore recommend that patients with osteoarthritis of the carpometacarpal joint of the thumb are offered a similar programme in addition to access to accessories and splints preoperatively.