This volume contains the proceedings of the international symposium on the durability of disease resistance in plants. Durability of resistance in plants is a highly desired quality influenced, among other things, by the adaptability of the pathogen populations, cultivation methods, phytosanitation and the kind of resistance used. The chapters cover a wide variety of subjects, ranging from the analysis of some of the world's most important pathosystems; the genetic variation in pathogen populations and the variation in the hosts; the present efforts at breeding durable resistance, viewed from both the biotechnological and the classical approaches, is also covered. This volume provides an opportunity for all those scientists, breeders and pathologists who are interested in the durability of disease resistance to obtain an insight into the research that is currently going on world-wide.