This book provides an essential guide to the use of the EuroQol Groups value sets for anyone working with EQ-5D data. The EQ-5D is one of the most widely-used generic health state descriptive systems internationally, with applications in clinical trials, public health research and assessments of value for money. In addition to providing a way of describing health and health improvement, the EQ-5D facilitates the valuation of health and health gain through its pre-existing value sets, spanning a wide range of countries and continents. This book brings together, for the first time, a comprehensive inventory of these value sets and their characteristics. Further, in response to frequent requests from users of EQ-5D data for advice on valuation, the book provides clear guidance to users on how to choose which value set to use, for what purpose.