In May 2023, the Zero-Dose Learning Hub's (ZDLH) Learning Innovation Unit (LIU), held its first inter-country peer learning exchange, “ZDLH-X,” focused on zero-dose (ZD) and under-immunized (UI) children and missed-community challenges in Bangladesh and Mali. The session provided an opportunity for national and sub-national practitioners from the two countries to share their experiences and learn from each other, and to strengthen networking within and across countries. This learning exchange focused on the “identify” and “reach” aspects of Gavi’s IRMMA Framework (Identify, Reach, Monitor, Measure, Advocate). A wide range of strategies have been adopted to identify and reach ZD/UI children and missed communities, addressing both supply- and demand-side barriers.