The Annual Conference of the European Association for Computer Science Logic, CSL 2001, was held in Paris, Palais de la Mutualit' e, on September 10-13, 2001. This was the 15th in a series of annual meetings, originally intended as International Workshops on Computer Science Logic, and the 10th to be held as the Annual Conference of the EACSL. The conference was organized by La- ratoire Sp' eci?cation et V' eri?cation (CNRS & ENS Cachan). The CSL 2001 program committee selected 39 of 91 submitted papers for presentation at the conference and publication in this proceedings volume. The submittedpapersoriginatedfrom26di?erentcountries.Eachpaperwasrefereed by at least three reviewers. In addition to the contributed papers, the scienti?c program of CSL 2001 - cluded three invited talks (Jean-Yves Girard, Peter O'Hearn, and Jan Van den Bussche). This volume includes the papers provided by the invited speakers as well as the selected contributed papers. The topics of the papers include: linear logic, descriptive complexity, semantics, higher-order programs, modal logics, veri?cation, automata, ?-calculus, induction, equational calculus, and constr- tive theory of types.
I am most grateful to the members of the program committee and all the referees for their thorough work. I am also particularly indebted to Fran, cois Laroussinie, helped by Patricia Bouyer, Nicolas Markey, and Philippe Schn- belen, for the successful organization of this event. Special thanks to Emmanuel Fleury for the design of the beautiful "Notre-Dame de Paris" poster.