This unified treatment of curve and surface design concepts is the Fourth Edition of the popular text, Curves and Surfaces for Computer-Aided Geometric Design, Third Edition (Academic Press, 1992). Assuming only a background in calculus and basic linear algebra, this revised and updated classic is highly accessible and should be of interest to a wide audience; from computer graphics hobbyists to software developers for CAD/CAM systems. The author's informal style makes this book very reader-friendly, and the IBM disk included in the back of the book will allow the user to gain first-hand experience with the concepts as they are explained. This book focuses on Bezier and B-spline methods for curves, rational Bezier and B-spline curves, geometric continuity, spline interpolation, and Coons methods. In this Fourth Edition, the content has been thoroughly revised and updated to include a new chapter on recursive subdivision, new material on nonrectangular topology, surface faceting, stereo lithography, and new sections on triangulations and scattered data interpolants. The disk provided in the back of the book has also been updated to include all of the data sets and the C code used in the book.