Political participation can take shape in many types of participation, between which the overlap is low. However, the similarities and differences between various types of participants are surprisingly understudied. In this article, I propose to differentiate between four types of participants: institutional political participants, non-institutional political participants, civic participants, and political consumers. These types differ from each other on two dimensions: whether they are political or publicly oriented and whether they are formally or informally organized. Building on the matching hypothesis, I argue that we should differentiate those four types of participants by their outlook on society (societal pessimism, political trust, and social trust). Using data from the European Social Survey 2006, including participants from 19 countries, logistic regressions show that institutional political participants trust politics rather than people, non-institutional political participants are societal pessimists who trust other people, civic participants are societal optimists who trust other people, and political consumers are pessimists who do not trust politics.