This tool is a one-page PDF of a Geographical Information System (GIS) map that was produced through Boston Public Health Commission's Record Management System. The tool allows public health officials to meet the state and federal mandated reporting requirements. The system collects and examines data produced during its mass vaccination campaign. Each person vaccinated is given a unique identifier. Limited patient medication and demographic information is also collected. Patient address information is used to produce GIS maps of the city indicating vaccine receipt by census block. These maps have been used by the Commission's planners to monitor coverage in Boston's neighborhoods--an important feature given that outbreak intensity has varied by neighborhood. This tool was submitted as part of an H1N1 Story from the Field. The story can be found at this link: http://www.naccho.org/topics/H1N1/h1n1story.cfm?story_id=327