Two forms of medicine complement one another in trying to alleviate the suffering associated with diseases and injuries, and sometimes also to reduce the risk of dying while sick. One form, traditional medicine, is old and richly varied. The other, biomedicine, is comparatively new, having appeared in the late nineteenth century, and specific. People have long turned to traditional medicine in the effort to relieve suffering, and they continued to do so after the appearance of biomedicine. The new medicine has much greater efficacy in certain areas. But the behavior of people across the world suggests that they continue to find comfort and relief in traditional medicine. They may consult folk or alternative practitioners, and they may go to their doctors in search of traditional treatments. A thriving arena of traditional medicine consists of self-treatment: people diagnose their own ailments, especially ones they deem minor, select treatments, and try to make themselves well. In this chapter the issue is not the history of medicine but the history of medicine's contribution to the health transition in a world of dramatically different medical and health cultures. In some cultures good health is a physical issue, in others an issue of the spirit, and in still others a mixture of body, emotions, and soul. Across cultures both traditional medicine and biomedicine have helped reduce mortality and the incidence of many diseases.