Nowadays sandwich constructions recommend themselves as an alternative to conventional structures in every field of structural engineering. The increasingly competitive market, especially in the marine sector, demands low prices and innovative products. Sandwich constructions can help to reach this objective. In a general sense every layered surface structure can be regarded as a sandwich structure. In the narrower and actual sense, a sandwich structure consists of three layers, the two faceplates and the core. Many different sandwich plate systems are available; and the options for others are countless: Two different materials joined by an appropriate technology result in a new sandwich plate. Choosing the right materials and tailoring the dimensions, lead to a sandwich plate that is optimum for the requirements from the specific application.