Research in Health Economics has developed into a separate discipline during the last 25 years. All this intense research activity has come about through the teaching of courses on health economics, mostly at graduate level. However, the Industrial Organization aspects of the health care market do not occupy a central place in those courses. The authors propose a textbook of health economics whose distinguishing feature is the analysis of the health care market from an Industrial Organization perspective. This textbook will provide teachers and students with a reference to study the market structure aspects of the health care sector. The book is structured in three parts. Part I presents the basic principles of economics. It brings all readers to the required level of knowledge to follow subsequent parts. Part II reviews the main concepts of health economics. Part III contains the core of the book. It presents the industrial organization analysis of the health care market, based on the authors' own research.