The Logic Colloquium 2004, the European Summer Meeting of the Association for Symbolic Logic, was held in Torino, Italy, 25–31 July 2004.

With more than 280 participants from all over the world, ten one-hour plenary lectures, four tutorials (three hours each), a panel discussion, three special sessions (with 20 speakers), and more than 200 contributed talks, the Logic Colloquium 2004 managed to present a broad spectrum of ideas, results, techniques, and problems in current research in logic.

The Program Committee consisted of: Toshiyasu Arai, Warren Goldfarb, Greg Hjorth, Dick de Jongh, Steffen Lempp, Gabriele Lolli, David Marker, Tony Martin, Ralph McKenzie, Wolfram Pohlers (Chair), Wilfried Sieg, Andrea Sorbi, and Alex Wilkie.

The Local Organizing Committee consisted of: Alessandro Andretta (Chair), Stefano Berardi, Riccardo Camerlo, Ugo de'Liguoro, Mariangiola Dezani, Alberto Marcone, Nicola Olivetti, and Domenico Zambella.

The meeting was organized by the logicians at the Dipartimento di Matematica and Dipartimento di Informatica of the University of Torino and was held at the Centro Congressi dell'Unione Industriale.

Sponsors. We would like to express our sincerest thanks to the following institutions, which, with their generous financial support, made this meeting possible. First and foremost, the Association for Symbolic Logic, which gave us the opportunity to organize the meeting and supported many students and post-docs with travel grants.