Henny J.M. Bouwmeester graduated cum laude from the University of Groningen (The Netherlands) in 1982. From the same university he received his Ph.D. degree on the basis of a dissertation titled: ‘Studies in Intercalation Chemistry of Some Transition Metal Dichalcogenides. For a period of three years he was involved with industrial research in the development of the ion sensitive field effect transistor (ISFET) for medical application at Sentron V.O.F., in the Netherlands. He joined the University of Twente in 1988, where he is now Associate Professor in Inorganic Membranes/Materials Chemistry. Dr. Bouwmeester is co-editor of the CRC Handbook of Solid State Electrochemistry. His research interests include solid state thermodynamics and electrochemistry, mixed conducting membranes, defect chemistry, oxygen surface exchange and electrode kinetics, and catalysis, in which fields he authored and co-authored several book chapters and more than 100 research papers.