Is cleanliness next to godliness? What does such a concept really mean? Why does it recur as a universal theme across all societies? And what are the implications for the unclean? In Purity and Danger Mary Douglas identifies the concern for purity as a key theme at the heart of every society. In lively and lucid prose she explains its relevance for every reader by revealing its wide-ranging impact on our attitudes to society, values, cosmology and knowledge. This book has been hugely influential in many areas of debate – from religion to social theory. With a specially commissioned preface by the author which assesses the continuing significance of the work, this Routledge Classics edition will ensure that Purity and Danger continues to challenge, question and inspire for many years to come.