This work presents a general approach to address the complex process of lightweight design for mechatronic systems. The approach is based on standard methodologies of product development and the fundamental idea of establishing an interdisciplinary concept design that directs the entire following and more detailed design process. The general process and its subsequences are introduced theoretically and highlighted by the exemplarily execution of the approach in a real development project. Moreover, it is demonstrated that the presented approach has a large potential of mass reduction by supporting the creation of novel lightweight design solutions. Its scope of application, the ability to achieve high product maturity and its drawbacks, including the time-consuming execution or the difficult realization of the whole optimization potential of a solution concept, are discussed. Basic design principles, lightweight materials and the state-of-the-art structural integrity concepts of lightweight design are furthermore presented with their applications illustrated. The presented thesis is split into three sections. First, an overview of the historical evolution of today's product development methodologies is given, including short introductions of some popular representatives such as the Value Engineering, the Systems Engineering and the Engineering Design. Furthermore, their similarities and general trends are outlined. Second, the chosen general approach to process the multidisciplinary conceptual and structural design of lightweight elements in mechatronic systems is introduced. The approach is presented in details with the main procedure, the analysis of the given design task and the definition of objectives, the conceptual design based on interdisciplinary investigations, the discipline-specific design based on the established concept, and the final integration of the discipline-specific solutions to the superior interdisciplinary solution and its verification. Fundamentals of tools for the treatment of the single process steps are provided and clarified. Finally, the multidisciplinary design approach is illustrated by a practical example from the aviation industries, represented by a real development process of a novel aircraft overhead stowage compartment for single-aisle aircraft. The stowage compartment is movable and electrically driven, i.e., a mechatronic system. The design process of the stowage compartment, starting with the design task and ending with the physical prototype and its validation, is presented stepwise and highlighted with representative examples. The work concludes with the presentation of an overhead stowage compartment designed according to the discussed design approach, for which a patent is requested and currently pending in Austria.