A trade association is a millennium-old organizational form that has existed on all continents. It is a private, formal, nonprofit organization designed to promote the common interests of its members, even if these members are competitors on product (or research) markets. While it is straightforward to assume that an association creates net benefits for its members – why would they join, otherwise? – it is unclear whether, or under which circumstances, the existence of an association has positive net effects for the rest of the economy. In “Trade Associations, Lobbying, and Endogenous Institutions,” Maria Larrain and Jens Prüfer study this question by means of a game-theoretic model. The answer is, of course, “it depends.” But on what does it depend? And why?