This paper describes a framework for involving schools in primary and secondary prevention of eating disturbances. The issues of why, what, who, and how are considered. Research on the prevalence and consequences of obesity, anorexia and bulimia nervosa, unhealthy dieting, and behaviors such as binge eating and purging indicates why prevention is necessary. Research on the etiology of eating disturbances also provided a basis for determining what factors need to be addressed. However, research has not adequately addressed the question of who should be targeted for prevention and how the topic of prevention should be approached. While different approaches to school-based prevention programs are possible, a comprehensive school-based program is recommended. Important components of a comprehensive program include staff training, classroom interventions, integration of relevant material into existing curriculum, individual counseling and small group work with high risk students, referral systems, opportunities for healthy eating, modifications within the physical education program, and outreach activities. This type of comprehensive program is based on an ecological model for health promotion and aims at the modification of both individual and environmental determinants of behavior.