Anaesthesia for surgery during armed conflict was traditionally based on simple and reliable techniques. These often required a minimum of equipment and drugs while ensuring rapid and safe patient recovery. Ketamine, which first became available in Britain in the 1970s, was thought to offer certain favorable characteristics for use as a military anaesthetic agent. This article discusses the use of ketamine in many of the major armed conflicts that have occurred since its introduction. It also catalogues the methods used by anaesthetists at the time and their opinions of the drug's success.