Analogous to gynecological fertility diagnostics as applied to women, the andrological methodology for the examination of men has been expanded into a simple and extended method of fertility diagnostics. Generally, the examination of a male patient begins with simple fertility diagnostics and is followed-up individually by detailed diagnostic procedures only when a certain suspicion exists. As a rule extended diagnostic procedures are not applied to a husband before the wife's ability to conceive has not first been determined at least by a simple gynecological examination. This proceeding sequence is rational and satisfying particularly since some fertility diagnostic interventions can only be imposed upon a patient after all other possibilities are exhausted. Primarily in cases of cohabitational disorders caused by male impotence, a similar diagnostic method is applied. As in the case of fertility examinations, all other possibilities, such as endocrinological malfunctions, metabolic disorders, disease symptoms and neurological defeciencies are thoroughly investigated. After all pathological findings are ruled out, psychoanalytical tests are advised. In most cases, behavioural disorders can be left to the guidance of the andrologist within the framework of minor sexual-psychological psychiatry. In more severe cases, specialized psychiatric diagnostic procedures are recommended. Although the classic spermiogram is still the focal point of diagnostics, normo-zoospermia is no longer necessarily synonymous with reproductive ability. Under given circumstances, differential diagnostic considerations are sometimes necessary taking the entire equipment of extended diagnostic procedures for granted.