The Undergraduate Medical Education for the 21st Century (UME-21) project was implemented by the Division of Medicine, Bureau of Health Professions, Health Resources and Services Administration (HRSA) to encourage medical schools to collaborate with managed care organizations and others. The purpose of the collaboration was to ensure that medical students are prepared to provide quality patient care and manage that care in an integrated health care system in which the cost of care and use of empirically justified care are important elements. The UME-21 project represents a continuation of HRSA's interest in the managed care arena. The UME-21 project involved the collaboration of eight partner schools and 10 associate partner schools, together with 50 external partners, to develop innovative curricula that integrated UME-21 content from nine special areas as learning objectives. This project demonstrated that concerted efforts by the leadership in medical education can bring about innovative change in medical school curricula. It ís also demonstrated that faculty of the three primary care disciplines of family medicine, general internal medicine, and general pediatrics were able to cooperate to accomplish such change by working together to allocate clerkship time and content. An important lesson learned in this project was that significant innovations in medical school curricula could be accomplished with a broadbased commitment and involvement of both faculties across the three primary care disciplines and top administrative officials of the medical school. It is uncertain, however, if the innovations achieved will produce further changes or if those changes achieved can be sustained without continued funding.