Background: The NATO hospital classification of hospitals describes an orderly transfer of patients with severe injuries through a series of increasingly sophisticated hospitals as they are brought from the point of injury to their home hospital. Forward hospital surgery is restricted to damage control and resuscitation while definitive surgery is performed at home by the destination surgical team. In reality many patients enter the hospital chain higher up and some receive definitive surgery as they proceed through the chain of evacuation. The purpose of this paper is to determine if clear doctrine exists to guide the performance of surgery on patients during their evacuation and to review current research in this area. Method: A systematic review of medical literature was combined with a review of military textbooks, handbooks and clinical guidelines. Results: Over 35,000 military personnel have been evacuated during recent conflicts in Iraq and Afghanistan. Factors associated with a reduced rate of return to duty included: combat injury (76% less); musculo-skeletal disorder (54% less); other wound (46% less) among other factors studied. Almost 3,000 civilians have been evacuated at the same with similar outcomes except for a poorer return to work after combat injury. Coalition forces use different chains of evacuation, dependent probably on distance: direct transfer home from forward hospital (UK); wing-to-wing transfer home (Holland); staged transfer through Role IV/V hospital (USA, Canada). Comparison of outcomes for each evacuation chain has not been made. Transfer within the home country has not been studied. Medical literature consists of several groups of papers categorized as follows: increasingly sophisticated surgical care in more forward hospitals, drug resistant infections, neurological and mental health issues, and critical care transport. There were no reports with respect to outcomes of surgery performed to keep personnel in theater. Impression: Care of combat injuries is changing. More definitive surgery is being performed before patients reach their destination hospital, either along the evacuation chain or within the home country. Research is required to determine if these changes benefit the patient or the mission.