The management of ankle injuries has long been a stumbling block for orthopae- dists in training. As a first year resident, I was fortunate to encounter the series of articles by N. Lauge-Hansen and T. Baek Kristensen that classified ankle injuries according to their mechanism. I found this information quite helpful throughout my residency and early years of practice. Several years ago, an attempt was made to summarize this material for the benefit of the orthopaedic house staff of Thomas Jefferson University. It quickly become obvious that such a manual would require a great deal of professional illustration and editorial assistance in order to be effective. Almost simulta- neously, a fortuitous encounter with Ms. Marie Low (at that time Medical Editor of Springer-Verlag New York Incorporated) provided both the stimulus and the means to present this information in the manner and detail which it deserved. Contributors were carefully selected for their kwledge and experience in particular areas and for their willingness to cooperate in providing a smooth- flowing manuscript. This text contains little new material. Rather, it represents an attempt to bring together, under one cover, the wealth of extant information on this subject. Wherever a consensus could t be perceived, conflicting views have been sum- marized as objectively as possible. Unfortunately, there are still many aspects of ankle injury for which we have more questions than answers.