The book begins with a historical overview of early FN self-loading rifles, all of which were discontinued not because of inherent problems but because of external events-usually wars-the overwhelming import of which took precedence over further development. After the German occupation of Belgium in 1940, the British seized upon FN's new gas-operated self-loading rifle and beginning in 1943, RSAF Enfield manufactured at least 51 examples of what was generally known as the SLEM (Self-Loading Experimental Model). Following the liberation of Belgium in late 1944 the self-loading rifle project was revived by FN, with comparative trials being conducted by the Royal Dutch Navy in 1947. The first commercial contract for what became the "FN49" was signed with Venezuela in 1948. Further orders from a number of countries were forthcoming over the next decade, leading to a total production of approximately 176,000 FN49s. We present new colour images of a complete collector's catalogue of all the contract models, in chronological order, which sheds new light on the developmental history of this fine arm. It contains extensive details on the development of the Echo scope mount, which was designed and patented by the American gunsmith and machinist Edward Herkner, whose story is told largely in his own (previously unpublished) words. The numerous component differences between the semi-automatic FN49 (the "SAFN") and the selective-fire version, the "AFN", are illustrated and explained. Two chapters cover combat use of the FN49 by the Belgian Volunteer Battalion in Korea and by Belgian and colonial troops (the Force Publique) in the Congo. A detailed retrospective production includes the complete, official FN Order List, plus further breakdowns of production and deliveries by year and by calibre. The book concludes with three chapters on Accessories and Ancillaries- handbooks, bayonets, cleaning kits, grenade launchers, scopes and slings-and a Bibliography.