This volume is a report of the proceedings of an International Symposium on Bladder Cancer and a selection of Urological papers presented at the Antwerp Medical Days in Antwerp, Belgium, on the 19th and 20th September 1980. The meeting was sponsored by the Antwerp Medical Days Program Committee supported by the Royal Antwerp Circle of Medicine, the Urological Group of the European Organization for Research on the Treatment of Cancer, the Belgische Vereniging voor Urologie, the Societe Belge d'Urologie, the Province and City of Antwerp and the National Fund for Scientific Medical Research of Belgium. Contributors were briefed to avoid too much overlapping, in the hope of obtaining a coherent compilation of clinical data. We are grateful for their discipline which enables early publication. All the contributions in this volume, except ~he section on immunology which was selected by the editors for its related inter­ est, were presented at the International Symposium under the sections 'Understanding the Disease', 'Therapeutic Approaches', 'Chemotherapy', and 'Prospective Studies'.