The invention of the interlocking nail has broadly extended the indications for reamed intramedullary nailing. It has even become the treatment of choice for most complex femoral shaft fractures. At Chang Gang Memorial Hospital, about 180 femoral cases have been treated with this technique each year since December 1986. With this accumulation of experience, both theoretical and clinical advancements are continuously developing and are regularly reported in the literature. In this article, experiences in the past few years with this technique are reviewed and evaluated. The author believes that to be a good trauma orthopedist, through training in femoral interlocking nailing, both theoretically and technically, is absolutely imperative. This device does, however, still have some disadvantages, but further improvements are anticipated with the advance of modern science.