This volume, dedicated to Prof. Gabriele Veneziano on the occasion of his retirement from CERN, starts as a broad historico-scientific study on the work on string theory and nonperturbative QCD that has been pioneered by Prof. Veneziano in the late 60s and early 70s. It goes on to examine the many ramifications this and similar early work has spawned over the past decades and the reader will find state-of-the art tutorial reviews on string cosmology, string dualities and symmetries, and much more.

The book includes a concise updated scientific biography of, and an interview with, Prof. Veneziano, in which he relates his personal views about the present and future of fundamental physics. This is followed by the commented draft of an unpublished paper of 1973 of his, anticipating interesting results which were rediscovered and published more than a decade later.

Overall, this volume is a vast and unique canvas where the re-examination of older and the presentation of newer results and insights are skillfully mixed with personal recollections of the contributing authors, most of them involved in the early days of string and quantum field theory, about Prof. Veneziano and the many interrelated topics considered.

This book has been prepared to celebrate the 65th birthday of Gabriele Veneziano and his retirement from CERN in September 2007. This reti- ment certainly will not mark the end of his extraordinary scienti?c career (in particular, he will remain on the permanent sta? of the Coll` ege de France in Paris), but we believe that this important step deserves a special celebration, and an appropriate recognition of his monumental contribution to physics. Our initial idea of preparing a volume of Selected papers of Professor Gabriele Veneziano, possibly with some added commentary, was dismissed when we realized that this format of book, very popular in former times, has become redundant today because of the full "digitalization" of all important physical journals, and their availability online in the electronic archives. We have thus preferred an alternative (and unconventional, but probably more e?ective) form of celebrating Gabriele's birthday: a collection of new papers written by his main collaborators and friends on the various aspects of th- retical physics that have been the object of his research work, during his long and fruitful career.