One thousand consecutive non-pathological intracapsular hip fractures, seen from 1961 to 1970, were analyzed. Of these, 754 were treated with Knowles pinning, and 160, with primary prosthetic replacement. An average of twenty-five months' follow-up was obtained in 70 per cent of the patients with Knowles pinning. The low in-hospital morbidity (7 per cent), mortality (1.3 per cent), and infection (0.5 per cent) rates in the patients who had Knowles pinnings were compared with the relatively high morbidity (24 per cent), mortality (11.3 per cent), and infection (16 per cent) rates in those who had primary femoral-head replacements. Fifteen per cent of the displaced fractures resulted in non-union and 12 per cent of the healed displaced fractures had significant segmental collapse. The purpose of this report is to emphasize the role of percutaneous Knowles pinning as a safe, simple, and reasonably effective method of treatment of most non-pathological intracapsular hip fractures. Our technique of percutaneous Knowles pinning is described and the development of the Knowles pin is reviewed.