This book seeks to distil and bring together the best available information on the lightest of the German World War II tank models, the PzKpfw I and //. Although the least spectacular of German tanks, these types formed the larger part of the German armoured force's strength when it scored its most crushing victories, in Poland in 1939 and in France and the Low Countries in 1940. Given the plethora of books on German armour it is surprising how badly documented is the story of the PzKpfw I and //. A study of the sources, both original and secondary, seemed to raise as many problems as it settled. The new and excellent 'Encyclopedia of German Tanks of World War If by Chamberlain, Doyle and Jentz, which appeared shortly before the book went to press was helpful on several points but I do not entirely agree with its authors in all cases and it does not solve all puzzles. In the following I try to offer the most detailed exposition of the development and service of the PzKpfw II yet available in English. It is hoped that it will be followed in due course by similar studies of other German models of tank, assault gun and S.P. equipment.