Biochemical Aspects of Plant-Parasite Relationships is a collection of papers from the Phytochemical Society Symposium of the same subject held at Hull in April 1975. This collection discusses biochemical research on the mechanisms involved in the invasion of plants by pathogens, the production of disease symptoms, and the mechanisms occurring in plant resistance against the invading microorganisms. Some papers discuss the genetics of fungal-plant interactions and the structural features of both infection and resistance processes, Such genetic interactions and structural features point to a biochemical reason for the plant-parasite interaction. Several attempts to correlate production of a cell wall degrading enzyme in vitro by a pathogen's virulence have shown great differences between in vitro and in vivo environments. One paper cites as an example the pathogens which produce both pectic hydrolases and lyases: the type of enzyme that is found to predominate often is actually associated with the pH of the environment. One paper also investigates nucleic acid transfer and the possible role of RNA in the host-parasite specificity. This collection can prove beneficial for microbiologists, biochemists, biotechnologists, plant biologists, and academicians connected with the biological sciences.