Gastrointestinal outbreaks cause serious obstruction to duty among military personnel. Early detection and effective surveillance of an outbreak is important for implementation of controls. SWAP is web based tool (www.swap.lanl.gov) that can be used to enhance situational awareness during an outbreak. We have collected information for about 100 gastrointestinal outbreaks caused by five different pathogens. The SWAP library contextualizes an unfolding epidemic using historical data. In addition, analyses were performed to assess the ability of SWAP to identify military outbreaks, and results indicate SWAP is successful in matching military outbreak properties. We are currently investigating SWAP's ability to identify the cause of an outbreak (food/pathogen) from the epidemiological characteristics of historical outbreaks.