The Zero-Dose Immunization Program (ZIP) is a Gavi initiative designed to reach children in humanitarian settings where government health services are inaccessible. Active in countries such as South Sudan, Ethiopia, and Chad, ZIP delivers life-saving vaccines to children in conflict zones, displaced populations, and nomadic communities. By working beyond government reach, ZIP ensures full immunization coverage through agile programming, local partnerships, and neutral humanitarian access, addressing the unique challenges of children living in vulnerable and high-risk environments.