Because public health problems affect schools and communities so pervasively, schools inevitably must alter their mission to act as important service delivery sites for public health services, as well as for some community primary health services. Learning comes easier to healthy children, and health problems interfere with learning. Psychologists' expertise in understanding and changing behavior provides a valuable tool to remedy behavioral health problems. The most serious and expensive health and social problems that affect the nation today are caused in large part by behavior patterns established during youth. Psychologists, who have scientific knowledge about behavioral health and expertise in prevention and intervention, are well prepared to contribute to the amelioration of these costly social problems. Psychologists are uniquely prepared to help provide comprehensive health, education, social and preventive services in schools and communities. Their expertise in research provides an important tool for ensuring the effectiveness and efficiency of these services. Specific contributions of psychology to critical aspects of school health, and school health care reform are presented. Chapters are: (1) Why Health is Important to Education and Schools; (2) Why Psychology Is Important to School Health; (3) The Roles Psychologists Can Play in School Health; and (4) Psychology's Response to Comprehensive School Program Components. Contains 24 references. (JBJ)