This book argues that critical realism offers the theory of cognitive rationality a real way of overcoming the limitations of methodological individualism by recognising both the agents' - and the social structure's - causal powers and liabilities. Cynthia Lins Hamlin persuasively argues that critical realism represents a better safeguard against the relativism which springs from the conflation of social reality and our ideas about it. This is an important book for sociologists and anyone working in the social sciences, and for all those concerned with the methodology, and philosophy, of social science.