The primary purpose of control is to force desired behavior in an unpredictable environment, under often-arbitrary disturbances and initial conditions. Thus tracking and tracking control synthesis are fundamental control issues. Surprisingly, however, tracking theory has not been well developed, and stability theory has dominated. This book presents the fundamentals of tracking theory for control systems. It introduces the full transfer function matrix, which changes the theory of linear dynamical and control systems and enables a novel synthesis of tracking control that works more effectively in real conditions.