Thermodynamics is one of the foundations of science. The subject has been developed for systems at equilibrium for the past 150 years. The story is di?erent for systems not at equilibrium, either time-dependent systems or systems in non-equilibrium stationary states; here much less has been done, even though the need for this subject has much wider applicability. We have been interested in, and studied, systems far from equilibrium for 40 years and present here some aspects of theory and experiments on three topics: Part I deals with formulation of thermodynamics of systems far from...