According to a popular version of social capital theory, civic engagement should produce generalized trust among citizens. We put this theory to the test by examining the causal connection between civic engagement and generalized trust using multiple methods and multiple (prospective) panel datasets. We found participants to be more trusting. This was mostly likely caused by selection effects: the causal effects of civic engagement on trust were very small or nonsignificant. In the cases where small causal effects were found, they turned out not to last. We found no differences across types of organizations and only minor variations across countries.