The book describes one of the successful efforts of the new German Navy, the Reichsmarine, to continue their research and lead in construction for the period when it would be allowed to possess submarines again. This meant by-passing the articles of the Treaty of Versailles that forbid such activities after 1919. The Germans moved expertise and factories to former neutral countries, e.g. the Netherlands. The interests of both countries were fully served by the Engineer firm/Ingenieurburo for Shipbuilding/Schiffbau IvS/Inkavos from 1922-1940. From 1940-1945 the activities continued under German supervision. In 1945 IvS was taken over by the Dutch Government and closed only in 1957.