The Spirit Level: Why More Equal Societies Almost Always Do Better is a book by Richard G. Wilkinson and Kate Pickett, published in 2009 by Allen Lane. The book is published in the US by Bloomsbury Press (December, 2009) with the new sub-title: Why Greater Equality Makes Societies Stronger. It was then published in a paperback second edition (United Kingdom) in November 2010 by Penguin Books with the subtitle, Why Equality is Better for Everyone.

The book argues that there are "pernicious effects that inequality has on societies: eroding trust, increasing anxiety and illness, and encouraging excessive consumption". It claims that for each of eleven different health and social problems: physical health, mental health, drug abuse, education, imprisonment, obesity, social mobility, trust and community life, violence, teenage pregnancies, and child well-being, outcomes are significantly worse in more unequal countries, whether rich or poor. The book contains graphs that are available online.

ABOUT THE AUTHOR:

.RICHARD G. WILKINSON: Richard Gerald Wilkinson (born 1943) is a British social epidemiologist, author and advocate. He is Professor Emeritus of Social Epidemiology at the University of Nottingham, having retired in 2008. He is also Honorary Professor of Epidemiology and Public Health at University College London and Visiting Professor at University of York. In 2009, Richard co-founded The Equality Trust. Richard was awarded a 2013 Silver Rose Award from Solidar for championing equality and the 2014 Charles Cully Memorial Medal by the Irish Cancer Society. 

.KATE PICKETT: Kate Pickett (born 1965), FRSA is a British epidemiologist who is Professor of Epidemiology in the Department of Health Sciences at the University of York and was a National Institute for Health Research Career Scientist from 2007-2012. She is a co-founder of The Equality Trust. Kate was awarded a 2013 Silver Rose Award from Solidar for championing equality and the 2014 Charles Cully Memorial Medal by the Irish Cancer Society.