This study is concerned with the collective consequences of social rules. The theoretical analyses take as a starting point the notion of 'new institutionalism' in the social sciences. The analyses focus on the nature and societal role of institutions, and more specifically social security institutions: the 'rules of relief' that are constructed by the community. Among other things, those institutions lay down the benefit entitlements that people enjoy and the duties that have to be fulfilled in order to enjoy them. The empirical analyses explore some of the effects of modern social security institutions. The central question is which collective outcomes are generated by the social security rules in 11 countries. The analyses first investigate whether the institutions differ from each other to such an extent that the national systems can in practice be said to represent three different types of social security: the liberal, the corporatist and the social-democratic model.