PKDD 2001, the 5th European Conference on Principles of Knowledge Discovery in Databases (PKDD),
was held in Freiburg, Baden-Württemberg, Germany, this year (Monday 3 to Thursday 7 September), and co-located with the 12th European Conference on Machine Learning (ECML 2001). The proceedings comprised two volumes, one for PKDD (De Raedt & Siebes, 2001) and one for ECML (De Raedt & Flach, 2001); and form part of the Springer Lecture Notes on Artificial Intelligence (LNAI) series. The conference was held in the University buildings in the centre of the old town. Freiburg and the surrounding area were for many years part of the Austro-Hungarian empire and thus the university was described to us as being one of the oldest Austrian Universities.