The present volume is a tribute to Gian-Carlo Rota. It is an anthology of the production of a unique collaboration among leading researchers who were greatly influenced by Gian-Carlo Rota's mathematical thought.The book begins with an essay in mathematical biography by H. Crapo in which the prospects for research opened up by Rota's work are outlined. The subsequent section is devoted to the prestigious Fubini lectures delivered by Gian-Carlo Rota at the Institute for scientific Interchange in 1998, with a preface by E. Vesentini. These lectures provide the only published documentation of Rota's plans for a fundamental reform of probability theory, a program interrupted by his untimely demise.The lectures by M. Aigner and D. Perrin specially conceived for this volume, provide self-contained surveys of central topics in combinatorics and theoretical computer science; they will also be of great use to both undergraduate and graduate students.The essays and research papers that appear in the final section present recent developments of some of the mathematical themes promoted by Gian-Carlo Rota. These will be of particular interest as they propose many new problems for research.

This book, dedicated to the memory of Gian-Carlo Rota, is the result of a collaborative effort by his friends, students and admirers. Rota was one of the great thinkers of our times, innovator in both mathematics and phenomenology. I feel moved, yet touched by a sense of sadness, in presenting this volume of work, despite the fear that I may be unworthy of the task that befalls me. Rota, both the scientist and the man, was marked by a generosity that knew no bounds. His ideas opened wide the horizons of fields of research, permitting an astonishing number of students from all over the globe to become enthusiastically involved. The contagious energy with which he demonstrated his tremendous mental capacity always proved fresh and inspiring. Beyond his renown as gifted scientist, what was particularly striking in Gian-Carlo Rota was his ability to appreciate the diverse intellectual capacities of those before him and to adapt his communications accordingly. This human sense, complemented by his acute appreciation of the importance of the individual, acted as a catalyst in bringing forth the very best in each one of his students. Whosoever was fortunate enough to enjoy Gian-Carlo Rota's longstanding friendship was most enriched by the experience, both mathematically and philosophically, and had occasion to appreciate son cote de bon vivant. The book opens with a heartfelt piece by Henry Crapo in which he meticulously pieces together what Gian-Carlo Rota's untimely demise has bequeathed to science.