Reaching zero-dose children—those who have not received any routine vaccines—remains a central priority under Gavi’s 6.0 strategy and the Immunization Agenda 2030. Achieving this goal requires not only identifying what works to reach missed communities, including those in migrant, displaced, and other vulnerable populations, but also knowing which strategies are efficient, context-appropriate, and sustainable within broader primary health care (PHC) systems.
Despite growing operational experience under Gavi 5.0, a critical gap remains in economic evidence to guide decision-making. Given the evolved donor landscape and fiscally constrained setting in many low- and middle-income countries, it becomes increasingly important to ask:
To support resource allocation decisions around how best to reach, vaccinate, and retain zero-dose children across diverse settings, we have compiled the growing body of research, tools, and convenings material focused on answering these questions.

Co-developed by the Zero-Dose Costing Working Group, this document outlines a set of research principles for studies that aim to estimate the cost of reaching zero-dose children.
Any organization or individual working in the field of immunization economics can submit findings, opportunities, calls to action, or other relevant work below to be shared with our community.