Special operations - in this context, commando or guerilla activities - conducted by the U.S. Army in World War II have been the subject of a good many thrilling adventure stories but little sober, historical analysis. Only a handful of works have examined the critical issues underlying special operations, and the Army’s historical series on World War II treats the subject only in passing. Yet special operations had a significant role that should not be ignored. Ranger units captured positions critical to the success of amphibious landings in the Mediterranean, France, and the Philippines. Partisans advised by American military personnel provided essential intelligence to American forces and harassed enemy troops in support of American operations in Italy, France, the Philippines, and Burma. As special operations forces grow in importance within the U.S. Army, we need to look at our experience with such activities in World War II. I recommend this study as an overview for Army leaders and other interested parties of an important, but often misunderstood subject. It fills a gap in the Army’s history of World War II and honors individuals whose efforts, frequently unsung, nevertheless made a major contribution to the American and Allied victory in that war. Harold W. Nelson Brigadier General, United States Army Chief of Military History