Medical care available to astronauts on the International Space Station has been affected by limitations on funding, space and weight availability, and crew training. A Space Medicine Patient Condition Database (PCDB) was designed to enhance inventory control, resource selection, protocol standardization, evidence-based medicine, on-orbit diagnostic skills, and materiel management. The first step in the PCDB creation was the identification of the medical conditions anticipated among the astronaut population in the flight environment. Military databases, previous spaceflight experience, and analog populations were used to create this listing. The PCDB then linked these individual conditions with the current resources available on orbit to treat them. Other features include a resource gauge, item location information, diagnosis coding, and built-in reference capabilities. Currently in the second phase of development, specific, evidence-based treatment protocols are being developed and evaluated in comparison with the terrestrial medicine standard of care. By documenting on-orbit medical systems and their associated terrestrial standards, the PCDB enables the prioritization and allocation of limited resources. In the final phase of the project, the PCDB will make use of decision support software to enhance diagnostic determination and provide an operational tool for the crew and mission teams.