The concept of Social Capital suggests that societies with more dense social networks will have more effective political institutions, be more cohesive and display stronger economic performances. However the causal foundations of this influential model have not been closely examined. The evidence put forward in Putnam's analysis of the Italian regions is critiqued. An empirical assessment of the model in relation to EU member states is carried out. Although the data fit the model, an alternative Equality model is statistically stronger as well as intuitively more appealing. The reasons for the strong appeal of the Social Capital model despite its weaknesses are discussed.