This volume contains the proceedings of the meeting Genetics and Alzheimer's Disease held in Paris, on March 25,1988, by the Fondation Ipsen pour la Recherche Therapeuti que. This meeting was the second of the series of Colloques Medecine et Recherche devoted to Alzheimer's disease. The first one was held in Angers (France) on September 14, 1987; the proceedings of this meeting have already been published and are entitled Immunology and Alzheimer's Disease (1988, edited by A Pouplard-Barthelaix, J Emile, and Y Christen). The third Colloque Medecine et Recherche, organized in Montpellier on Sep tember 19, 1988, dealt with neuronal grafting; the proceedings of this last meeting will be published in early 1989 (Neuronal Grafting and Alzheimer's Disease: Future Perspectives, edited by F Gage, A Privat and Y Christen). In each case, the Fondation Ipsen deliberately focuses attention on the most up-to-date themes, and sometimes the most controversial ones, from medical and scientific research. The genetic aspects of Alzheimer's Disease (AD) stands at the very forefront of research carried out in the last 2 years. It complements research using the formal approach, which has become possible thanks to the study of extended kindreds by J-F Foncin and other scientists. The recent work on molecular and genetics biology has followed two main pathways: 1. The study of the gene(s) responsible for the familial form(s), which can be considered the AD gene(s).