ThyssenKrupp Marine Systems is the undisputed world market leader in non-nuclear submarine technology. During the last five decades, numerous nations have decided in favour of high-tech submarines "made in Kiel". ThyssenKrupp Marine Systems enjoys close and cooperative relations with navies worldwide. It is an evident proof of confidence that many navies have placed repeat orders in Kiel. The company does not only support the purchase of new submarines, but also offers overhauls and modernisations of boats that have been in service for an extended period of time.