Despite high national coverage rates in Zambia, pockets of inequities exist. These inequities are driven by geographic and sociodemographic factors (including wealth, rural or urban slum residence, number of children in the household, and education of mothers) that result in households and/or communities continuing to be missed. Many zero-dose (ZD) children live in households that are missed by the formal health sector altogether. Strategies, especially at the micro-level, are needed to identify those that have been previously missed so they can be reached with services. Geographic Information System (GIS) technology offers a potential solution because it can aid in the development of detailed, accurate maps, often revealing households or communities that had not been known previously; identify micro-level variations in coverage that had been obscured using more aggregated data; and allow for modeling and prediction, such as predicting how coverage would be affected if vaccination sites were added.