This proceedings volume consists of selected papers presented at the Ninth Int- national Conference on Computer-Aided Scheduling of Public Transport (CASPT 2004), which was held at the Hilton San Diego Resort and Conference Center in San Diego, California, USA, from August 9-11, 2004. The CASPT 2004 conference is the continuation of a series of international workshops and conferences prese- ing recent research and progress in computer-aided scheduling in public transport. Previous workshops and conferences were held in: Chicago (1975) Leeds (1980) Montreal (1983 and 1990) Hamburg (1987)...