Over the past twenty-five years I have built-up an externally funded research programme with a strong equipment base. This has been achieved through a balanced combination of individual and collaborative grants and contracts. The focus of my research is in applying chemical engineering to problems in the area of catalysis and high temperature membranes. While the emphasis is very much on applied research, often a fundamental understanding of the nature of the problem is necessary. I have published more than 100 refereed papers, supervised around 40 PhD students. Much of my research involves working with inorganic membranes. In many cases solid oxide materials can exhibit very high ionic conductivities (e.g., oxygen-ion or proton conductivity). If, at the same time, the electronic conductivity of the material is very low the material can be employed as a solid electrolyte. If the electronic conductivity is high, the material can be used as a mixed-conducting membrane. My research involves the application of both solid electrolytes and mixed-conducting membrane systems for reaction and separation.