Thermodynamics provides part of the scientific infrastructure needed to evaluate the course and rate of corrosion processes. Its principle value is in yielding information on intermediate products of the complementary anodic and cathodic partial reactions that together constitute a complete process. The chapter discusses thermodynamics of aqueous corrosion which includes oxidation and reduction processes in aqueous solution and oxidation states, and presents kinetics of aqueous corrosion. In the long term, the degradation of engineering metals and alloys by corrosion is inevitable and so resistance to it is essentially concerned with the rates of corrosion. The polarization characteristics for an electrode refer to the relation between current and applied potential, including activation, concentration and resistance contributions. The chapter provides information on thermodynamics and kinetics of dry oxidation, oxidation of metals forming cation interstitial oxides, cation vacancy oxides and anion vacancy oxides.