The research activity is divided in four steps. The first step defines the technical terms and compiles the basic principles. The following second step contains a list of already realised noise protection systems subdivided according to their performance and building material. In the third step the different systems are evaluated with regard to technical aspects and shape. Possible synergies in using different protection systems coevally and aspects of safety to traffic are discussed. In the fourth step, based on the resulting findings of the third part, optimised noise protection systems on existing as well as on new bridges are outlined.