This book is the result of an informal association between the editors which extends back to 1974. At the beginning, it was a tenuous alliance between physicians in quite different medical subspecialties-urology and psychiatry. As the alliance was forged, subspecialty rivalries and mistrust were replaced by a common clinical interest in the diagnosis and treatment of erectile problems. We quickly became aware of the high prevalence of such disorders, how poorly prepared we were to make accurate and re­ sponsible diagnosis and treatment plans, and how complicated an etiol­ ogical diagnosis could prove to be. A variety of biological and psychological influences bear on sexual function, and in many clinical contexts, diagnosis and treatment planning involves consideration of complex interactive var­ iables. The need for an expanded multidisciplinary team became obvious. The requisite knowledge base extended across too many subspecialty boundaries, and the necessary information was not available in a conve­ nient source. As we began accumulating the information base, we became aware that this information might be of value to other physicians. The authors enjoy the luxury of an academic setting in which special expertise can be readily assembled. Such resources are often unavailable to the physician in practice. Thus, it is our hope that this text can serve as a multi specialty team for the physician in solo practice. R. TAYLOR SEGRAVES New Orleans, Louisiana HARRY W.