The book outlines a new approach to the synthesis of nonlinear dynamic systems a key problem in control engineering. The suggested design formalism is based on the "binary" principle which is essentially a dual treatment of signals in the dynamic system - as a phase variable in one circumstance and as a transformation operator in another. This principle opens up the possibility of handling control laws as ordinary phase variables and invokes feedback to generate such laws. The feedback mechanism in this case is exploited in a nonorthodox manner, leading to the occurrence of new types of feedback. The efficiency of the new approach is demonstrated by constructing control systems which stabilize motion of nonlinear dynamic plants with ill-defined dynamics. The stabilization is attained with continuous control and bounded gains. Apart from solving the problems of ill-defined plant control, the binary principle is used to advantage for the development of nonlinear filters separating close frequencies, for multiple differentiating noisy signals, and for control of multiconnected systems. The value of the binary principle is not confined to the control field, rather it may be employed in studies of complicated dynamic systems in biology, biomechanics, social sciences, robotics, and biotech engineering, to name a few of the most promising applications.