Madigan Army Medical Center, a Military Treatment Facility (MTF) in Washington State, adopted the next generation electronic medical record, MHS GENESIS, in 2017. With this go-live, transmission of immunization data between the MTF and the Washington State Immunization Information System (WAIIS) ceased. Sharing this data allowed public health officials to more accurately assess immunization status and population health risk. Inclusion of external data helped to ensure complete immunization records of individuals treated at the MTF. We developed this project to facilitate information sharing between MHS GENESIS and the WAIIS. Parallel efforts aimed to both restore the basic flat-file functionality previously existing as well as establish a bi-directional HL7 interface.