In June 1987, neurobiologists, immunologists, molecular biologists, virologists and neurologists from several countries met in Vancouver to discuss recent advances of relevance to multiple sclerosis. The symposium was a part of the 22nd Canadian Congress of Neurological Sciences meeting and was sponsored by funds from the Multiple Sclerosis Society of Canada and the Medical Research Council of Canada. The presentations covered five major topics: basic neurobiology, molecular biology, the role of viruses in demyelination, immune function and dysfunction in multiple sclerosis, and clinical magnetic resonance imaging studies. It was heartening to note that scientists from several different disciplines were working towards a common end-point: the understanding and treatment of multiple sclerosis. In this book, speakers at the symposium have each presented a chapter of their findings and discussions. In addition, some non-participants at the symposium have been invited to submit chapters in order to give this volume a more complete scope. It is hoped that the reader will find this book a useful reference for several subjects of interest to multiple sclerosis. In closing, I would like to thank the following for their help and support: the Multiple Sclerosis Society of Canada and the Medical Research Council of Canada for their financial support; the contributors of this book for their manuscripts; Dr. A. Eisen, Mrs. K. Eisen, Mrs. P. Bodnarchuk and Mrs. M. Kim for their efforts in planning and organizing the symposium; and Ms. Catherine Schikowski for her secretarial assistance. Seung U. Kim, M.D. Ph.D.