There is a clear trend in rich countries that, despite rising incomes and living standards, the gap between rich and poor is widening. What does this mean for our health? Does increasing income inequality affect outcomes such as obesity, life expectancy and subjective well-being? Are rich and poor groups affected in the same ways? This book reviews the latest research on the relationship between inequality and health, and provides a pedagogical introduction to the tools and knowledge needed to understand and assess the vast literature on the subject. The book includes discussion of the definitions and measurement of objective and subjective health and income inequality, and illustrates how various measures have been developed in different countries. Main conclusions from the literature are then summarized and discussed critically. It incorporates a substantial research overview of the field, as well as a detailed debate of the empirical challenges that arise during research. The book concludes that results are surprisingly contradictory, but that several studies have found that higher inequality is directly linked to lower subjective well-being. Students and scholars in public health, social work, economics, and sociology will find this book an essential exposition of conceptual issues and empirical methods applied to the controversial topic of the health consequences of inequality.