14 January 2014In this paper we provide evidence that trust and reciprocity, the two key elements of social capital, are affected by country differences. Based on the amounts sent and returned in the investment game by student subjects we find evidence on trusting and reciprocal behaviour and we show significant cross-country differences between the levels of trust and reciprocity. We also show that the answers for ‘trust in strangers’ type attitudinal questions have a significant effect either on trusting or reciprocal behaviour, while gender does not affect any of them. We report that reciprocity is affected by the same variables as trust: in particular stated trust has a significant influence on reciprocal behaviour, which can be explained by attitudes such as projective reasoning. Furthermore, we find that questionnaire based rankings of countries are poor predictors of trusting behaviour rankings, which is mainly due to the differences in strength of correlation between stated trust and trusting behaviour country-by-country.