W. Harmon Ray is Vilas Research Professor and past chairman of the Department of Chemical Engineering at the University of Wisconsin in Madison. He received his B.A. and B.S.Ch.E. from Rice University and his Ph.D. from the University of Minnesota in 1966. Before joining the University of Wisconsin he was a faculty member at the University of Waterloo in Canada, from 1966 to 1970, and at the State University of New York at Buffalo, from 1970 to 1976. Professor Ray has had extensive industrial consulting experience, and has contributed numerous articles to the technical literature in the areas of polymerization processes, chemical reaction engineering, process modelling, optimization, and process dynamics and control. He is co-author of a monograph, Process Optimization, published in 1973, and author of Advanced Process Control which appeared in 1981. This latter book has been published in Russian and Chinese. Professor Ray is also co-editor of two volumes: Distributed Parameter Systems (1978), and Dynamics and Modelling of Reacting Systems (1980). More recently, he is the coauthor of the textbook, Process Dynamics, Modeling, and Control (1994). In 1969, Professor Ray received the D. P. Eckman Award of the American Automatic Control Council and spent a year, in 1973-74, as a Guggenheim Fellow in Europe. In 1981 he received the Arthur K. Doolittle Award of the Organic Coatings and Plastics Division of the American Chemical Society and also the Automatica Prize Paper Award of the International Federation of Automatic Control. In addition, he was the recipient of the 1982 Professional Progress Award of the American Institute of Chemical Engineeers. In 1989 Prof. Ray received the Control Education Award from the American Automatic Control Council. Professor Ray has been a distinguished lecturer at a number of universities including the Lacey Lectures at Caltech, the Reilly Lectures at Notre Dame, the Kelley Lecture at Purdue, and the Sargent Lecture at Imperial College London. Prof. Ray is a Fellow of AIChE, and a member of the National Academy of Engineering.