This paper provides an interpretation, based on the social systems theory of German sociologist Niklas Luhmann, of the recent paradigmatic shift of mental health care from an asylum-based model to a community-oriented network of services. The observed shift is described as the development of psychiatry as a function system of modern society and whose operative goal has moved from the medical and social management of a lower and marginalized group to the specialized medical and psychological care of the whole population. From this theoretical viewpoint, the wider deployment of the modern social order as a functionally differentiated system may be considered to be a consistent driving force for this process; it has made asylum psychiatry overly incompatible with prevailing social values (particularly with the normative and regulative principle of inclusion of all individuals in the different functional spheres of society and with the common patterns of participation in modern function systems) and has, in turn, required the availability of psychiatric care for a growing number of individuals. After presenting this account, some major challenges for the future of mental health care provision, such as the overburdening of services or the overt exclusion of a significant group of potential users, are identified and briefly discussed.