The demand for bigger,faster and lighter moving ve hicles,such as ships,trains,trucks and buses has increased the importance of efficient str uctural arrangements. In principle two approaches exist to develop efficient structures:e ither application of new materials or the use of new structural design. A proven and well-establi shed solution is the use of composite materials and sandwich structures. In this way high strength to weight ratio and minimum weight can be obtained. The sandwich structures have potential to offer a w ide range of attractive design solutions. In addition to the obtained weight reduction,these so lutions can often bring space savings,fire resistance,noise control and improved heating and cooling performance. Laser-welded metallic sandwich panels offer a number of outstand ing properties allowing the designer to develop light and efficient structural configuratio ns for a large variety of applications. These panels have been under active investigations during the last 15 years in the world.