The purpose of this book is to provide readers with a single source reviewing and updating developments in theories commonly used today in medical or health sociology. The first edition originated in papers and discussions in a session on new developments in theory in medical sociology at the International Sociological Association’s 2010 World Congress of Sociology held in Gothenburg, Sweden. The session was scheduled because theoretical work had increasingly become a major feature of medical sociology. Much of the work was atheoretical when the field first appeared as a new sociological specialty in the mid-twentieth century. Over time, this situation changed dramatically, and this book’s task was to not only discuss the major theoretical approaches that had emerged but also to identify new directions in theory in medical sociology. This second edition continues this theme.