“Integrating Vertical Programs into Primary Health Care: A Decision-Making Approach for Policymakers” offers practical guidance for policymakers who need to make decisions about whether and how to more fully integrate specific vertical programs into their country’s broader health system, with a focus on PHC. It discusses what the evidence shows about the successes and failures of such efforts, considerations for policymakers when making decisions about integration, and ways to balance potential gains and losses. It also proposes use of a tool called the PHC Conceptual Framework for characterizing the relationship between a vertical program and the broader system and exploring the potential opportunities and constraints that come with integration. The Annex includes brief case studies from South Africa and Ethiopia illustrating how the framework can help to understand integration efforts.