Nuffield College has the largest number of sociologists of any college in Oxford, including the two University Chairs in Sociology. The Sociology Group at Nuffield lies at the heart of Sociology in Oxford. In addition to sociologists, the Sociology Group in Nuffield includes social statisticians, demographers, and social historians. The principal specialities of the Nuffield sociologists are analytical sociology, medical sociology, political sociology, social networks, social stratification, the sociology of labour markets, family sociology, pro-social behaviour, and sociology of religion. The group is particularly strong in the development and empirical testing of middle-range social-science theories.