Canadian society of 20 years hence will be characterized by population growth and turbulence; great population density; further applications of new technology; persistent concentration of ethnic minorities; growth of large-scale, impersonal bureaucracies and organizations; and deterioration of large population centers. The rates of offenses related to drugs, white-collar crime violent behavior, and organized crime are expected to increase considerably. In response to the changing nature of crimes, police departments will be forced to intensify investigative efforts. As financial transactions will transpire mostly through money transfers without checks or cash, and as criminals will be even more mobile than today, police will have to expand their organizational structure in the areas of information and communications in particular. The structure of the organization will have to be redesigned to deal with increased urban crime and more frequent investigations. A high educational level as well as new training norms, especially for the social sciences, will have to be established for personnel. Furthermore, continued research and development efforts are needed to assist police management in ascertaining the directions of change. A great deal of information is available that might be useful in answering the many questions about future trends, but much of the valuable information of government agencies at all levels is lost in the bureaucracy. Nevertheless, it remains certain that crime rates will rise and that the police will continue to combat crime. To achieve success, the population at large must participate actively in police prevention programs. No references are cited. -- in French.