General Fritz von Lossberg (1868--1942) directed virtually all the major German defensive battles on the Western Front during the First World War. Hailed as "the Lion of the Defensive," he was an extremely influential military tactician and, unlike many other operations officers of his era, was quick to grasp the changes wrought by technology.

Now available for the first time in English, Lossberg's memoir explains how he developed, tested, and implemented his central principles -- flexibility, decentralized control, and counterattack -- which were based on a need to adapt to shifting...