The main theme of this book is robust control design from a practical point of view. A thorough introduction to frequency response norm-based robust control design methods is given. This includes, in particular, a comprehensive treatment of the structural singular value . An important problem in robust control design is how to determine model uncertainty. In this book it is shown how system identification can be used to obtain error bounds for use in subsequent controller design. Both classical prediction error methods and the more recent Stochastic Embedding Approach are treated and a step-by-step procedure for system identification based robust control design is provided. The design techniques presented in the book are illustrated through numerous case studies including, for example, the control design for an ASTOVL (Advanced Short Take-Off and Vertical Landing) aircraft.