The Joint Theater Trauma Registry is a standardized, retrospective data collection system for all echelons of combat casualty care. Military-specific data elements include expanded demographic data to include military branch, service, rank, military occupation, and personal protective equipment. Varying data from each echelon are entered into the Joint Theater Trauma Registry, version 3. The Joint Theater Trauma Registry, version 3 at the echelon 4 medical treatment facility requires routine collection of 367 data elements for each casualty, but casualties sustaining burns, deaths, or those with performance improvement issues may have more than 450 data elements recorded. Trauma registries are powerful tools for process improvement. Collaboration between civilian and military trauma programs may foster improvements in registry design and data collection for both groups.