This volume contains the Proceedings of the 4th International Conference on Ticks and Tick-borne Pathogens (TTP-4), held in Banff Alberta, Canada, from 21 to 26 July 2002. TTP-4 continues an important tradition established in 1992 at the first Conference in St Paul Minnesota, USA, and developed subsequently at the Kruger National Park, South Africa (1995) and the High Tatra Mountains, Slovakia (1999). The 31 papers published in this special issue are divided between six sessions, with a keynote address as an introduction. The first session, which deals with biosystematics, genomics and proteomics of ticks, contains the most recent world list of valid tick names in 2003. The papers deal with a broad range of tick-host-pathogen interactions, including remote sensing and mapping of ticks and tick-borne pathogens as well as practical aspects of tick control. It is recommended reading for anyone working on ticks and tick-borne pathogens, which are of increasing medical and veterinary importance worldwide.