This paper reports the results of an experiment aimed at investigating the link between empathy, anticipated guilt, and pro-social behavior. In particular, we test the hypothesis that empathy modulates the anticipatory effect of guilt in bargaining situations and, more specifically, that it correlates with subjects' willingness to give and to repay trust in an investment game. We also control for the effect of individual risk attitude. Our main results show that empathy significantly influences players' pattern of restitution in the investment game and that risk-propensity weakly affects the decision to trust; we also find a significant gender difference in the distribution of empathy. These results seem to indicate that empathy affects pro-social behavior in a more complex way than previously hypothesized by existing models of social preferences.