Studies of social capital have concentrated upon either formal associative behaviour or informal social relations (networks). This article looks at the relationship between these two ty‘pes of social capital by examining social networks, social and family support (informal social capital) on the one hand and associational behaviour along with social trust (formal social capital) on the other. Using the Eurobarometer 62.2 covering a representative sample of 27 countries the analysis found that with this approach, regions in Europe can be grouped according to the two dimensions, whether they are high on both forms of social capital (complementarity) or whether informal social capital substitutes for formal social capital (substitution). The Scandinavian countries and the Netherlands had the highest levels of all forms of social capital. In the South and East of Europe informal social capital was more important, but whilst in the South this was mainly in the form of family support, in the East informal support outside the family was also important. Thus, we can speak of ‘social capital regimes’ to better understand the various cultures of participation and cohesion across Europe.