The Symposium on Topology, Geometry and Quantum Field Theory took place in Oxford during the week 24–29 June 2002. Graeme Segal's sixtieth birthday was celebrated at a special dinner; his mathematics throughout the meeting. These proceedings reflect the scientific excitement at the Symposium, which more than 140 physicists, geometers and topologists attended.

The Symposium was financially supported by the EPSRC, the London Mathematical Society and Oxford University. I would like to thank all the speakers, participants and everyone who helped with the organization for making the Symposium such a success. Special thanks are due to the contributors to these proceedings and the referees. Brenda Willoughby not only offered technical help in putting this volume together but also typed Part II more than ten years ago. Finally and foremost, I would like to thank Graeme Segal for his consent (if reluctant) to holding this Symposium in honour of his birthday, and publishing his influential manuscript as part of these proceedings.