The goal of this book is to present the new trend of Computational Fluid Dynamics (CFD) for the 21 st Century. It consists of papers presented at a symposium honoring Prof. No buyuki Satofuka on the occasion of his 60th birthday. The symposium entitled Computational Fluid Dynamics fOT the 21st Century was held at Kyoto Institute of Technology (KIT) in Kyoto, Japan on July 15-17,2000. The symposium was hosted by KIT as a memorial event celebrating the 100 year anniversary of this establishment. The invited speakers were from Ja pan as weil as from the international community in Asia, Europe and North America. It is a great pleasure to dedicate this book to Prof. Satofuka in appreciation ofhis contributions to this field. During the last 30 years, Prof. Satofuka made many important contributions to CFD ad vancing the numerics and our understanding of flow physics in different regimes. The details of his contributions are discussed in the first chapter. The book contains chapters covering re lated topics with emphasis on new promising directions for the 21 st Century. The chapters of the book reflect the 10 sessions of the symposium on both the numerics and the applications including grid generation and adaptation, new numerical schemes, optimi zation techniques and parallel computations as weil as applications to multi-sc ale and multi physics problems, design and flow control and new topics beyond aeronautics. In the follow ing, the chapters of the book are introduced.