CONSTRAINED-EQUILIBRIUM APPROACH TO NONEQUILIBRIUM DYNAMICS.

We review the constrained-equilibrium method for the description of the time-dependent behavior of dynamical systems in nonequilibrium states. The method is presented in a general mathematical framework that is relevant not only to thermodynamics and chemical kinetics, but also to economics, control theory and other sciences. We emphasize that a successful application of the method requires a deep understanding of the internal mechanisms governing the system dynamics and, in particular, their time scales and time invariants.