SLAM, the nickname for S. L. A. Marshall, is a scholarly but readable study of the controversial journalist/combat historian and his influence on the U.S. Army's training and doctrine. Most famous for his assertion that only 25 percent of infantry soldiers fired their weapons in World War II, Marshall became a lightning rod for criticism as he sought to reform the U.S. Army through his writings. The controversy has rarely been addressed as thoroughly as it is by F. D. G. Williams, who portrays a man in the right place at the right time. Marshall applied his group interview techniques to historical use. He developed what is now called after-action review, thereby contributing to the growth of the field of oral history; ensured that tons of primary source documents were preserved; and inaugurated the German officer interview program for collecting critical intelligence for the Cold War. The account reflects not only the experience of one man but also the positive movement by our fighting force, making it a great resource for combat historians today seeking to understand their role and mission.