The 1965 Lignite Symposium, the fourth in a series and the third sponsored by the University of North Dakota, and the Bureau of Mines, was held at Bismark, N. Dak., on April 29-30, 1965. These symposia provide a forum for those interested in the technology and utilization of solid fuels, especially lignitic coals. As part of the meeting, a 200-mile field trip was taken including inspection of (1) the 200-metawatt, pulverized lignite-fired Leland Olds plant of Basin Electric Power Cooperative, under construction near Stanton, N. Dak.; (2) the site of the Glenharold mine of the Truax-Traer Coal Co., Division of Consolidation Coal Co., where a wheel excavator was being assembled; (3) the operating Beulah mine of Knife River Coal Mining Co., subsidiary fo Montana Dakota Utilities Co., near Beulah, N. Dak.; and (4) the 400-megawatt, hydroelectric Garrison Dam powerplant, near Garrison, N. Dak. During the technical sessions, 13 papers were presented covering some the recent trends, development, and research in lignite technology. The text of these papers is compiled to provide a record of the symposium and to allow wider dissemination of the information. Proceedings of the previous symposia have been published.