In contrast to conventional lightweight material like aluminium or titanium, fiber composites offer the possibility to integrate functional elements directly into the material. Thus, multifunctional materials are developed which have the ability to serve more than the load-carrying function. As there is extensive work on the field of integration of thin piezoceramic plates and foils into carbon fiber reinforced polymeres, this will be focused on in this paper. First the design of an active carbon fiber composite with integrated piezoceramic is shown. Different fiber layups and connecting methods to supply the piezoceramic are discussed. A sophisticated processing technology for active composite materials, the so-called DP-RTM (Differential Pressure - Resin Transfer Moulding), is presented. Various damage mechanisms may reduce or even destroy the sensing and actuating capabilities of the piezoceramic material. Therefore the capability of high resolution non-destructive methods to evaluate manufacturing defects as well as defects resulting from mechanical overload is presented. Finally two applications are discussed in more detail to demonstrate the potential of the active composite material. Representing static applications an active composite plate is shown which has an,,infinite" bending stiffness up to a certain load. A second active composite plate is used for active noise control.