This article introduces the concept of orchestration as the mobilization of an intermediary by an orchestrator on a voluntary basis in pursuit of a joint governance goal. Orchestrator-Intermediary theory then provides a model of indirect governance that supplements delegation models premised on principal-agent theory. Under both theories, governors enhance their governance capacity by drawing on the capabilities of third parties. Whereas delegation is premised on hard ‘contractual’ control over the agent, however, orchestration relies on the soft control of like-minded intermediaries through material and ideational support. The two models overlap, and governors mix them in practice, but distinguishing between them analytically can broaden and deepen analysis of indirect forms of governance. This article discusses the circumstances under which each model provides a better fit for real-world problems, as well as the key limitations of each model. Among other things, orchestration is relatively more likely in democratic than authoritarian systems, when governors have limited direct capacities of their own and when veto players are more numerous. Orchestration is not always more desirable than delegation, but it provides an important alternative in some circumstances. Multiple examples from both domestic and international settings are used to illustrate this claim. The article closes with key considerations regarding the effectiveness and legitimacy of orchestration.