We report the results in 24 consecutive patients treated from 1976 to 1991 for nonunion of olecranon fractures. Their mean age was 42 years, and the mean interval from fracture to treatment for nonunion was 19 months. Management was by rehabilitation and activity as tolerated for three, continued immobilisation for one, and operative treatment for 20. Operations included excision of the olecranon fragment (1), osteosynthesis (16), and joint replacement (3). Four patients also had distraction arthroplasty. At a mean follow-up of 18 months no patient had severe residual elbow pain but three had moderate and six had mild symptoms. The mean arc of motion was 98 degrees representing an average improvement of 11 degrees. Twelve patients had an excellent result, four good, six fair, and two a poor result. Union had been achieved in 15 of the 16 patients treated by osteosynthesis.