Edited by Antoniou (International Solvay Institutes for Physics and Chemistry, Belgium; Aristotle U. of Thessaloniki, Greece), the volume includes 44 papers presented at the conference held in November 2001. It also contains opening addresses by the Greek Minister of Culture and J. Solvay, who comments on the 90-year history of the Solvary conferences' contributions to fundamental problems in modern physics. International contributions discuss challenging issues facing communication, information processing, and computation relating to quantum theory: e.g., irreversibility, nonlocality, and photonics. The volume includes photos of participants of the first and current conferences