'¬ÜComplexity'¬" for the past two decades has informed a range of work across the social sciences. There are diverse schools of complexity thinking and authors studying areas as diverse as health inequalities and the organization of large scale firms have used the ideas in a different ways. Some understand complexity as emergence from the rule based interactions of simple agents and explore it through agent based modelling. Others argue against such '¬Ürestricted complexity'¬" and for the development of case based narratives deploying a much wider set of approaches and techniques. Major social theorists have been reinterpreted through a complexity lens and the whole methodological programme of the social sciences has been recast in complexity terms. This book seeks to establish '¬Üthe state of the art'¬" of complexity informed social science as it stands now and point ways forward towards a post-disciplinary complexity informed social science for the 21st century