This document discusses advocacy strategies for sustainable immunization financing programs in Anglophone African countries. It outlines the social contract between citizens and their government, where citizens elect the government to manage resources and budgets on their behalf. Advocacy can come from endogenous groups seeking to influence the social contract, like citizens asking their government to prioritize immunization issues. Different institutional actors, like government agencies and parliament, follow different logics in their decision making. The document provides examples of effective advocacy, like demonstrating a program's cost-effectiveness to avoid budget cuts. Overall it examines how to formulate advocacy messages that fit the different logics of institutions to effectively make the case for increased immunization budgets.