The immunology of mucosal surfaces is one of the most exciting and relevant areas of medical veterinary and dental research since it applies basic research to tissues in- volved in everyday defence against microbes and against environmental and food antigens. This book is based on the contributions presented at the International Con- gress of Mucosal Immunology, held in London in July 1989 and organised by the Mu- cosal Immunology Affinity Group of the British Society for Immunology. The meet- ing was attended by over 500 delegates from 27 countries, including virtually all of the leading investigators in the field. The contents give comprehensive and up-to- date information on such topics as antigen presentation and processing in the gut, mucosal vaccines in man and animals, HIV infection in the gut, the role of yo T cells in the gut epithelium, recent advances in inflammatory bowel disease and coeliac dis- ease, the role of cytokines in the regulation of the IgA response, mucosal mast cells and cell migration. The contributions reflect the rapid pace of research in mucosal immunology, and the great strides which are taking place in the understanding of the immunology, molecular biology and biochemistry of host response at mucosal sur- faces.