Written on the same scheme than his well acclaimed first book, U.S. Army Infantry Divisions, 1943-45, this book is the first part of a two-volume series on the U.S. Armored Divisions in WWII. The U.S. Army committed in battle 16 armored divisions, but two of them stayed organized under the obsolete organization of 1942. This fact obliged the researchers to study both organizations to have a complete overview of the U.S. Armored Divisions in WWII. In this volume, the author presents an extremely detailed record of the organization, doctrine, and equipment of the Armored Divisions, after the reorganization of September 1943. A second volume will focus on the organization of 1942, and the 2nd and 3rd Armored Divisions. Yves Bellanger examines each unit and sub-unit of the division, from Division Headquarters to the Band. A chapter is dedicated to each principal unit: Tank Battalion, Armored Infantry Battalion, Armored Engineer Battalion, Division Artillery, but also Ordnance Maintenance and Medical Battalions. Rear-area units, generally overlooked or forgotten are also included. For each unit, the author examines their organization, down to the lowest level, and their training, drills, and tactical doctrine as described in contemporary field manuals. Each sub-unit, including section and squad, is presented by lists of personnel with rank and duty, individual weapons, vehicles with armament and radio sets, and organizational equipment, individual and common. At battalion and company levels, the author studies the doctrine of employment of the unit, in offensive, defensive, and special operations, as well as the duties of key personnel. The book includes 146 charts depicting the general organization of each unit but also a detailed organization showing all vehicles with crew members, on march, in combat, and at work when those positions are known. Charts also depict the radio nets from division level down to company level. In each section of the book, a special paragraph examines the changes and modifications made in the field by armored division’s units, as found in unit reports, unit histories, and veterans recollections. The volume concludes with a set of appendices, including the list of authorized tables of organization and changes on 1 September 1944, and a list of usual abbreviations. This is an essential reference for re-enactors, modellers, wargamers, researchers, and all those who require a detailed guide to the U.S. Armored Division during the 1943-45 period. It complements the author’s book series on the organization of U.S. Army divisions in WWII, which has begun with U.S. Army Infantry Divisions, 1943-45.