Interest in catalytic applications continue to grow in a variety of disciplines as researchers find even more links to other fields in basic science and in commercial applications. This collection of the 23 papers that serve as chapters here include recent work on metal oxides, including such topics as the molecular structures of surface oxide species, nanostructured supported metal oxides, defect chemistry and transport, surface processes and composition, the electronic structure of metal oxides, surface acidity and basicity, optical basicity, cation valence states analyzed by spectroscopy, investigation through methanol chemisorption, combinatorial approaches, methane oxidation, metathesis of olefins, applications of metal oxides for volatile organic compound combustion, selective catalytic reduction processes, gas sensors based on semiconducting metal oxides, and fuel electrodes for solid oxide fuel cells.