The third International Symposium on the Scientific Basis for Nuclear Waste Management was held in Boston, Massachusetts, on November 17-20, 1980, as part of the Annual Meeting of the Materials Research Society. The purpose of this Symposium was to provide an interdisciplinary forum for the discussion of scientific research dealing with all levels and types of radioactive wastes and their management. Since its inception in 1978, this annual Symposium has provided a unique opportunity for scientists of widely differing backgrounds to share in such discussions. The proceedings of the first two meetings were published as Volumes 1 and 2 in this series. The fourth Symposium is scheduled to be held in the autumn of 1981. The efforts of many people went into making this meeting a success. The scope of the 1980 Symposium was guided by the follow ing Steering Committee: K. J. Notz (Chairman), Oak Ridge National Laboratory, USA G. H. Daly, Department of Energy, USA D. E. Ferguson, Oak Ridge National Laboratory, USA R. H. Flowers, Atomic Energy Research Establishment, UK F. Girardi, Ispra Establishment, Italy T. Ishihara, Radioactive Waste Management Center, Japan R. W. Lynch, Sandia Laboratories, USA S. A. Mayman, Atomic Energy of Canada Ltd. , Canada G. J. McCarthy, North Dakota State University, USA E. Merz, Kernforschunganlage Jillich, FRG L. Nilsson, KBS Project, Sweden D. M. Rohrer, Nuclear Regulatory Commission, USA R. Roy, Pennsylvania State University, USA T. "E. Scott, Ames Laboratory, USA C.