Bob Kowalski was educated at the University of Chicago, University of Bridgeport (BA in mathematics, 1963), Stanford University (MSc in mathematics, 1966), University of Warsaw and the University of Edinburgh (PhD in computer science, 1970). He was a Research Fellow at the University of Edinburgh (1970-75) and has been at Imperial College London since 1975, attaining a chair in Computational Logic in 1982 and becoming Emeritus Professor in 1999. He began his research in the field of automated theorem-proving, developing both SL-resolution with Donald Kuehner and the connection graph proof procedure. However, he is best known for his contributions to the development of logic programming, starting with the procedural interpretation of Horn clauses. He also developed the minimal model and the fixpoint semantics of Horn clauses with Maarten van Emden. With Marek Sergot, he developed both the event calculus and the application of logic programming to legal reasoning. With Fariba Sadri, he developed an agent model in which beliefs are represented by logic programs and goals are represented by integrity constraints. He has also worked on the application of argumentation applied to default reasoning with Phan Minh Dung and Francesca Toni.