In this prospective randomised trial we compare the mortality, morbidity and functional results of patients following each of the three principal methods of treatment for displaced subcapital fractures of the femur. Two hundred and ninety patients over the age of 65 years were included and randomly allocated to undergo closed reduction and internal fixation with a sliding compression screw plate or uncemented Austin Moore hemiarthroplasty or cemented Howse II total hip arthroplasty (THA). Nineteen patients were subsequently excluded. The 13 year results show that there was no statistical difference in the mortality between the three groups (81, 85 and 91% respectively). Internal fixation and hemiarthroplasty groups fared poorly with a revision rate of 33 and 24%, respectively, compared with 6.75% in the THA group. The dislocation rate was 13% following hemiarthroplasty and 20% following THA. Average Harris hip scores were 62, 55 and 80, respectively, for the internal fixation, hemiarthroplasty and THA groups. In the long term, both internal fixation and hemiarthroplasty resulted in a poor outcome with respect to pain and mobility. Despite high early complications, THA resulted in least pain and most mobility both in the short and long-term and was encouraging with a revision rate of only 6.25%. THA should be seriously considered in physiologically active patients with a displaced subcapital fracture of the femur.