We are pleased to announce two special events that will be held in 2007, in Italy and France respectively, in honour of Jean-Yves Girard, who celebrates his 60th birthday this year: ************************* Workshop on Linear Logic, Ludics, Implicit Complexity and Operator Algebras. Dedicated to Jean-Yves Girard on his 60th birthday. University of Siena (Italy) at the Certosa di Pontignano, May 17-20, 2007. Organizing committee: Michele Abrusci (Roma III), Claudia Faggian (CNRS - Paris 7), Simone Martini (Bologna), Simona Ronchi Della Rocca (Torino), Aldo Ursini (Siena, chair) www.unisi.it/eventi/LOGIC ************************* and ************************* Journées Jean-Yves Girard Conference in honour of his 60th birthday Institut Henri Poincaré, Paris, September 10 and 11, 2007 Organizing committee: Michele Abrusci (Roma III) Pierre-Louis Curien (CNRS - Paris 7, chair), Martin Hyland (Cambridge), Giuseppe Longo (ENS, Paris), Mitsu Okada (Keio U., Tokyo), Phil Scott (Univ. of Ottawa), Jacqueline Vauzeilles (Paris 13, co-chair) http://www-lipn.univ-paris13.fr/jyg60 ************************* Both events will be an occasion to celebrate Jean-Yves Girard's deep achievements in Mathematics and in Computer Science, and the pervasive influence of his ideas in those disciplines and beyond. The Siena workshop also celebrates the 20th anniversary of the completion of his fundamental paper on Linear Logic. The aim is to gather people working in the many research streams originating from Girard's main achievements of the recent years. For each of the four main themes---Linear Logic (specifically, Proof Nets and Geometry of Interaction), Ludics, Implicit Complexity and Operator Algebras---there will be in-depth lectures (3 to 4 hours), with emphasis on the state of the art and prospects for future development. There will also be some time for 30- minute contributed papers and for discussion of general perspectives and philosophical foundations. This workshop has been organized to complement the celebration in Paris, which will take place immediately after Jean-Yves' birthday. Through our choice of invited speakers, we hope to illustrate the wide range of scientific interests of Jean-Yves Girard over thirty- five years, from the complexity of proofs to quantum mechanics, from system F to the geometry of computation, from denotational semantics to Von Neumann algebras. The two web sites will provide all details. Pierre-Louis Curien and Aldo Ursini