This article analyzes hybridity in third sector organizations (TSOs) in relation to the coproduction of public services. It begins by discussing hybridity in terms of the overlap between the third sector and other social institutions like the state, market, and community, illustrated by the welfare triangle. Then, it briefly introduces three different public administration regimes. It argues that changing from one area of overlap to another may place TSOs in an unfamiliar, or even alien, environment, resulting in increased hybridity and complexity. After it turns to coproduction and notes, it can refer to a variety of phenomena at various levels that contribute to the growing hybridity and complexity for TSOs and their leaders. It concludes that TSOs can orient themselves toward one of two main kinds of hybridity. A number of hypotheses are presented and some preliminary conclusions about the importance of coproduction for the governance of hybrid organizations are reached at the end of the article.