After an increase in the 1980s, incidence and mortality for prostate cancer in North America or England and Wales started to decrease in the early 1990s. The reasons for this evolution are widely debated, notably the importance of early detection. This study describes trends of prostate cancer incidence and mortality in 5 areas in France, where practices of early detection for this cancer are widely used. The 5 French administrative areas, covered by a population-based registry, have a total population of approximately 1,700,000 men. Incidence data from these registries were studied for the period 1982–1995, and mortality data were provided by the Institut National de la Santé et de la Recherche Médicale (INSERM) for the period 1982–1996. Age-Period-Cohort models by Poisson regression were created to characterize these trends. Between 1982 and 1995, 14,699 cases of prostate cancer were registered by the 5 registries under consideration. After a little intensification of the increase in 1987, undoubtedly due to early detection (notably using Prostate-Specific Antigen), the trend of the incidence seems to reverse from 1993. Mortality increased monotonically from 1982–1990 by an average of 1.8% per year, before decreasing annually by an average of 3.3% until 1996. Poisson regressions indicated a period effect on both incidence and mortality data; a small, but significant, cohort effect exists for incidence evolution, showing that elements such as etiologic factors may have an influence. Until results of randomized studies on mass screening are available, the question of individual screening remains; improved knowledge of risk factors could be interesting. © 2001 Wiley-Liss, Inc.