Abstract
Whereas it is assumed that involving users in the delivery of public services yields more positive evaluations of those services, this study shows that levels of satisfaction and trust are not necessarily positively affected by such user co-production. An experimental vignette design among students (n = 174) is used to analyze the differences concerning trust and satisfaction between co-produced and non-co-produced public services. In some cases, the results suggest, co-production actually leads to less satisfaction and trust. This might be explained by the self-serving bias, which states that co-producers take credit for success but blame service providers for failure.