The search by individuals and communities for ways to improve or maintain health and well-being is a fundamentally social process, shaped by history and values. The availability of different medicines or healing practices and the choices made by individuals to access them have varied over time and space and continue to do so. The Western biomedical model of health and disease has come to have a worldwide influence on health systems. Its dominance is illustrated by the use of terms such as ‘traditional’, ‘complementary’ and ‘alternative’ to describe ‘other’ healing systems, practices and products. However, the boundaries between all of these are far from clear and we will return to the question of definitions below. To date, much of the popular and policy debate on traditional medicine (TM) and complementary and alternative medicine (CAM) has focused on issues of efficacy and effectiveness, in line with biomedical research priorities, rather than on historical, social and legal aspects of practice. However, there is now a significant body of social and legal research that analyses the phenomenon of TM and CAM. We contend that health policy should be informed by the best quality research and this should include evidence from social science, not just medical science. The primary argument of the book is that the current popular and policy debates are concentrated in what is very much a polarized and largely asocial discourse (e.g. Ernst and Singh 2008) and that a multi-disciplinary social science (law, sociology, geography, history, ethics) perspective seeking to introduce nuance and theorize diversity in the field will provide a much more robust and context-sensitive evidence base for policy and practice in the field.