All readers will be aware of the changes in organisation and methods of the German Army between 1919 and 1939. The author of this groundbreaking work was ColGen Hans von Seeckt, who laid down the basis upon which Guderian, Rommel, Halder and others worked to produce the German Army of 1939. Every aspect of command in battle is covered, with exhaustive treatment of tactical and operational considerations. Even today the great majority of what is contained in this large work is applicable. This is accompanied by the Atlas zur Führung und Gefecht (published 1928) which summarises the whole tactical and operational concept in diagrammatic form. Any student of the German Army should seriously consider this work (and get a good German-English military dictionary to go with it).