Quantum Decoherence: Poincar?Seminar 2005

This volume is devoted to Quantum Decoherence with lectures from the S?minaire Poincar?, held in November 2005 at the Institute Henri Poincar? Paris. The goal of this seminar is to provide up-to-date information about general topics of great interest in physics. Both the theoretical and experimental results are covered, with some historical background. Particular care is devoted to the pedagogical nature of the presentation.