The increasing computational power available to control theorists and engineers is creating an enormous need for theoretical developments in nonlinear systems. In addition, the tools needed for analyzing and developing effective numerical methods for nonlinear problems are extremely difficult to create. This book presents a mathematically oriented introduction to the modern operator-theoretic approach to nonlinear feedback systems for engineers and others who wish tobecome familiar with the field. It presents a basic introduction to one of the two principal approaches to the theory of nonlinear control systems, (the other approach is a differential geometric approach), and assumes only a basic background in real andfunctional analysis. The authors have an outstanding reputation in the field, and the content of the book is timely. Written by foremost researchers in nonlinear analysis Focuses on the operator theory approach -not the differential geometric approach-to nonlinear control systems Covers key topics such as stability theory, robust stabilization in optimal design, factorization theory, and nonlinear system identification Features a chapter on the applications to neural and intelligent control Provides informative chapter exercises