Vasectomy is an effective measure preventing postoperative epididymectomy in prostatic and urethral surgery. The reasons why it proves sometimes ineffective are discussed. The stumps of the divided vas should be exteriorised in order to obviate complications which may arise when the stumps are burried in the scrotum. Various methods of temporary reversible occlusion of the vas were tried in prostatic patients as substitutes for vasectomy. The results of those attempts are presented. The technique of vasectomy is presented in which the stumps of the severed vas are exteriorised. Reasons for this procedure are given. Various methods were tried to produce temporary and reversible occlusion of the vas instead of vasectomy. The most promising way seems to be the ligature of the vas which is then exteriorised and wrapped with skinflap.