After World War II, the United States military increasingly found itself involved in operations that have been described variously as limited wars, small wars, low intensity conflicts, operations other than war, support and stability operations, and the like. The name common for such operations throughout much of the 1990s was operations other than war (OOTW). During this period there was an explosion of doctrinal material on the subject, including an official field manual, FM 100-5, which appeared in 1993 and listed six principles of OOTW: objective, unity of effort, legitimacy, perseverance, restraint and security. The author of the present work examines four successful OOTWs (the Greek Civil War, Lebanon, the Dominican Republic, and Nicaragua/Honduras) and four failed ones (Vietnam, Beirut, Somalia, and Haiti) and concludes that there is a positive correlation between adherence to the principles and the operation's outcome. Furthermore, the author suggests that some of the principles serve as necessary conditions for others.