ABSTRACT
I have been asked by the convenor, Keith Tinkler, to provide a brief afterword to this volume, based on my reading of the papers herein collected, and my participation in the symposium as a commentator on each paper after it was delivered. I would like to say a few words about each of the papers in the order in which it was given, and to suggest what seemed to me interesting questions, novel results, and possible avenues for future research.
