ABSTRACT
The small-gain theorem is an extremely useful tool for the analysis and control design of interconnected systems. This chapter introduces the first, fundamentally nonlinear variant of the small-gain theorem, known as the ISS small-gain theorem, as well as the related methods. With the ISS small-gain theorem, the ISS property of an interconnected system composed of two ISS subsystems can be tested by checking the composition of the ISS gains.
