Membership in certain intergovernmental organizations (IGOs), such as the World Trade Organization, has long been argued to stimulate trade. Yet, evidence linking IGOs to trade is mixed. We argue that identifying the influence of IGOs requires attention not only to the institutions IGOs enact, but to the network through which they enact them. We incorporate the full set of IGOs by using shared-IGO membership to create a network of connectivity between countries. This approach allows us to demonstrate that trade between two countries increases by an average of fifty-eight percent with every doubling of the strength of IGO connection between them. We also contribute to debates regarding the mechanisms through which structural relationships influence economic behavior by showing that substantial trade benefits occur not only through economic IGOs, but also through IGOs that were formed for social and cultural purposes, and that connections through IGOs that are organizationally strong have more impact than those through minimalist IGOs. The broader network formed by IGO connections is also important, as there is greater trade between countries that have dissimilar relationships to others. We reason that such dissimilarities in the IGO network create brokering opportunities, where trade between two poorly connected countries flows between a third that is better connected to both.