Anthropologists in Arms looks at the moral and ethical debates surrounding the recent development of 'military anthropology'--particularly the practice of embedding anthropologists with combat troops in Iraq and Afghanistan. Lucas traces the troubled history of social scientists collaborating with national military, security, and intelligence organizations and shows how these complex and frequently misunderstood historical concerns contribute to the contemporary moral controversy. He gives special attention to the Human Terrain Systems project developed by the U.S. Army under the direction of General David Petraeus. Although this project has been criticized as unethical by academic anthropologists in the U.S. and the U.K., Lucas shows that the moral status of that program is much more ambiguous than these blanket criticisms would suggest. Anthropologists in Arms concludes with a call for a thorough review of HTS itself, and suggests alternative strategies for providing anthropological knowledge to military forces engaged in irregular warfare--knowledge that might, in turn, help military forces to ameliorate the suffering imposed on noncombatants, while respecting the privacy, security, and human rights of indigenous populations.