Many mechanical systems are actively controlled in order to improve their dynamic performance. Examples are elastic satellites, active vehicle suspension systems, robots, magnetic bearings, automatic machine tools. Problems that are typical for mechanical systems arise in the following areas: – Modeling the mechanical system in such a way that the model is suitable for control design – Designing multivariable controls to be robust with respect to parameter variations and uncertainties in system order of elastic structures – Fast real-time signal processing – Generating high dynamic control forces and providing the necessary control power – Reliability and safety concepts, taking into account the growing role of software within the system The objective of the Symposium has been to present methods that contribute to the solutions of such problems. Typical examples are demonstrating the state of the art It intends to evalua~ the limits of performance that can be achieved by controlling the dynamics, and it should point to gaps in present research and areas for future research. Mainly, it has brought together leading experts from quite different areas presenting their points of view. The International Union of Theoretical and Applied Mechanics (l UTAM) has initiated and sponsored, in cooperation with the International Federation of Automatic Control (IF AC), this Symposium on Dynamics of Controlled Mechanical Systems, held at the Swiss Federal Institute of Technology (ETH) in Zurich, Switzerland, May 3D-June 3, 1988.