clinical aspects of andrology have not received similar emphasis. Since literature concerning clinical andrology is extensive and widely scattered in many different publica­ tions, we hope that a useful purpose will be served by summarizing the more pertinent material in a series of volumes which can be made readily available to students of andrology. It was decided that a series of specialized monographs should be devoted to clinics in andrology. These ten volumes of the series are an attempt to coordinate anatomical, physiological, biochemical, endocrinological, pharmacological and immunological aspects of the spermatozoa, testes, epi­ didymis and other accessory genital organs. Little is known about the effect of diet, diseases, environmental factors and drugs on male reproduction. The interest in developing new male contraceptive methods will stimulate research in andrology.