Excessive school absence is a major educational and social problem in the United States, yet very little is known about its etiology or how to prevent or ameliorate it. This paper reports results from a series of related studies conducted in seven Boston middle schools (grades 6, 7, and 8) to test the hypotheses that health problems and unmet health needs are major characteristics distinguishing excessively absent students from regular attenders and that a health-oriented approach using medically mediated interventions is effective in reducing absences among excessively absent students. There were no significant differences between regular attenders and excessively absent students on multiple measures of student and family health status, health habits, and health service utilization patterns in a case-control study. The intervention program was not associated with a significant decrease in absence school-wide or for participating students. We conclude that demographic and educational characteristics of students exert a greater effect on their behavior in regard to absence from school than do health status or receipt of health services and that a health-oriented approach, such as the one used here, will not have a major impact on what remains one of the most profound educational and social problems involving children in the United States today.