Several fundamental advances were announced at the Seventh International Symposium on Molecular Plant—Microbe Interactions held in Edinburgh in 1994. These included the cloning and identification of plant resistance genes involved in recognition of pathogens; the description of genetically engineered plants with novel resistance to pathogens; characterization of the molecular basis of pathogenicity of fungal and bacterial plant pathogens; and the mechanisms of communication used during recognition between symbiotic rhizobia and their host legumes. Participants in the Symposium contributed a series of papers that represent the leading edge of research in this important area of plant and microbial science. These articles are brought together to form this book, which will be essential reading for research workers, advanced students and others interested in keeping abreast of this rapidly developing area.