Psychosomatic medicine began as a social movement within medicine, designed to counteract the mechanistic and impersonal features that had accompanied the introduction of science into medical education. In its early days, therapeutic inefficacy led to a concentration upon understanding the origins of disorders in which emotional determinants played a role. To a large exten, psychosomatic medicine is still identified with such understanding. Within recent years, however, the development of increasingly effective therapeutic techniques has changed the emphasis in psychosomatic medicine from understanding to action. These developments are particularly well exemplified by the case of obesity. Social investigations have revealed that the prevalence of obesity within populations is determined to a very high degree by social factors, operating in an unplanned and uncontrolled manner...