The security issues set by the global digitization of our society have had, and will continue to have, a crucial impact at all levels of our social organization, including, just to mention a few, privacy, economics, environmental policies, national sovereignty, medical environments. The importance of the collaborations in the various ?elds of computer s- ence to solve these problems linked with other sciences and techniques is clearly recognized. Moreover, the collaborative work to bridge the formal theory and practical applications becomes increasingly important and useful. In this context, and since France and Japan have strong academic and ind- trial backgrounds in the theory and practice of the scienti?c challenges set by this digitized world, in 2005 we started a formal French-Japanese collaboration and workshop series on computer security. The three ?rst editions of these French-Japanese Computer Security wo- shops in Tokyo, September 5-7, 2005 and December 4-5, 2006 and in Nancy, March 13-14, 2008 were very fruitful and were accompanied by several imp- tant research exchanges between France and Japan. Because of this success, we launched a call for papers dedicated to computer security from it's foundation to practice, with the goal of gathering together ?nal versions of the rich set of papers and ideas presented at the workshops, yet opening the call to everyone interested in contributing in this context. This v- ume presents the selection of papers arising from this call and this international collaboration.

Jean-Pierre Jouannaud has deeply influenced, and is still influencing, research in Informatics, through the many important results he has produced in various research fields and through the generations of scholars he has educated. He has played a leading role in field of rewriting and its technology, advancing the research areas of unification, rewriting and completion modulo, conditional rewriting, termination proofs, modular properties, and automated proofs by induction in rewrite theories. Following his strong interest for algebraic specification languages and their efficient implementation, Jean-Pierre Jouannaud has contributed to the design, semantics and implementation of OBJ2 and has recently augmented the Maude rewriting logic system with an essential feature: membership equational logic. He was a member of the CNU (National University Council) and a member of the CNRS national committee. He is now heading with great success the computer science laboratory at the Ecole Polytechnique thus showing his exceptional qualities as a research team manager and supervisor of students.

This Festschrift volume, published to honor Jean-Pierre Jouannaud on his 60th Birthday on May 12, 2007, includes 13 refereed papers by leading researchers, current and former colleagues, who congregated at a celebratory symposium held in Cachan near Paris, France, on June 21-22, 2007. The papers are grouped in thematic sections on Rewriting Foundations, Proof and Computation, and a final section entitled Towards Safety and Security.

This book constitutes the refereed proceedings of the 15th International Conference on Automated Deduction, CADE-15, held in Lindau, Germany, in July 1998.
The volume presents three invited contributions together with 25 revised full papers and 10 revised system descriptions; these were selected from a total of 120 submissions. The papers address all current issues in automated deduction and theorem proving based on resolution, superposition, model generation and elimination, or connection tableau calculus, in first-order, higher-order, intuitionistic, or modal logics, and describe applications to geometry, computer algebra, or reactive systems.