The University Archives is pleased to announce that videotaped lectures from Don Knuth's computer science course Mathematical Writing (CS209), given in the fall of 1987, are now available online. The course focused on issues of technical writing and the effective presentation of mathematics and computer science. Guest lectures included Herb Wilf (University of Pennsylvania), Jeff Ullman (Stanford), Leslie Lamport (Digital Equipment Corporation) , Nils Nilsson (Stanford), Mary-Claire van Leunen (Digital Equipment Corporation) , Rosalie Stemer (San Francisco Chronicle), and Paul Halmos (University of Santa Clara). The class notes are available as a Stanford report, Mathematical Writing, and a published book.