What is the nature of the social reality? How do the major social institutions like money and law exist? What are the limits of individualistically-oriented social theories? These and related problems are intensely discussed in philosophy, in legal theory and in the methodology of social sciences. This collection brings together the different traditions of the contemporary discussions. It includes new and thought-provoking articles by John Searle, Margaret Gilbert, Ota Weinberg, Raimo Tuomela, Eerik Lagerspetz, Michael Quante, Maria Cristina Redondo and Paolo Comanducci.