The practical aspects in designing feedback control systems in which the plant may be nonminimum phase, unstable and also highly uncertain are emphasized in this book. The plant uncertainty features are closely related to what is today called ""robustness"". A major task in automatic control is to design a well-behaving feedback controlled system which stays ""robust"" and satisfies correctly defined quantitative performances for the entire region of uncertainty of the plant. ""Classical (QFT)"" and ""modern (Hoo)"" design approaches for that purpose are explained side by side and are used to solve similar design examples, so that results obtained by both approaches can be compared. From here stems the name of the book.