1. Introduction. 2. Ionic and Electronic Conduction of Solid and Liquid Oxides and of Other Ionic Compounds. 3. Relation between the Conductivity and Diffusivity of Ions in Oxides. 4. Diffusion of Ions in Solid and Liquid Oxides. 5. Transport Properties in Oxides with Multicomponents. 6. Equilibrium Electromotive Force of Galvanic Cells with Solid Electrolytes of Oxygen Anion Conduction. 7. Galvanic Cells with Electrolytes with Non-Oxygen Conduction. 8. Overpotential at Interface between a Metal and an Oxide with Ionic Conduction. 9. Electrochemical Kinetics at the Interface between Metals and Liquid Oxides with Ionic Conduction. 10. Industrial Application of Oxygen Sensors with Solid Electrolytes of Oxygen Anion Conduction. 11. Solid-Oxide Oxygen Sensors for the Steelmaking Industry. 12. Various Chemical Sensors with Solid Oxides. 13. Various Oxides used for Electronic Devices. Appendix. Subject Index.