We analysed retrospectively a series of 269 distal radius fractures in adults in order to determine which of five different classification systems gave the best information about the radiographical prognosis of a fracture. The result after reduction in 195 cases was influenced mainly by the primary shortening, whereas dorsal angulation, radial displacement, and the age and sex of the patient were of minor importance. The system described by Older et al. in 1965, was superior to the others. In the analysis of the radiographical result after fracture union, the quality of the reduction, the Older classification system, and the age of the patient were the most important prognostic factors. We conclude that reduction of a distal radius fracture should primarily aim at correcting the shortening.