It is obvious that digital rectal examination and assay of prostate specific antigen are required for all patients presenting signs of prostatism, but the true benefit of such an attitude for all patients is a matter of much controversy. We do know that the incidence of prostate cancer is rising faster than any other cancer and that the cause of death in approximately 3% of the male population over 50 years will be cancer of the prostate. Yet despite this risk, and due to the lack of satisfactory registries, the prevalence of the disease still remains unknown. A well-conducted mass screening programme could be expected to uncover prostate cancer in approximately 6% of the population, which would mean that in the French male population in the 55-70 year range, 348,000 cases would be diagnosed. Assuming that 70% of them would have a localized form theoretically accessible to curative treatment (radical prostatectomy or radiotherapy), the current mortality for prostatectomy (1 to 2%) would mean that at least 2,500 persons would die during the perioperative period. The question of psychological impact of a general screening programme and its cost are other considerations of importance. Under these conditions, can a mass screening programme be proposed? In France, the answer today appears to be no. The arguments in favour of early diagnosis are insufficient for mass screening and will remain so until a certain number of basic questions concerning the efficacy of treatment, the cost-benefit ratio of screening, and the psychological impact of early diagnosis are resolved.