Paul C. van Oorschot is a cryptographer and computer security researcher, currently a professor of computer science at Carleton University, where he holds the Canada Research Chair in Authentication and Computer Security. He is a Fellow of the Royal Society of Canada (FRSC). He is best known as co-author of the Handbook of Applied Cryptography (ISBN 0-8493-8523-7), together with Alfred Menezes and Scott Vanstone. Van Oorschot was awarded the 2000 J.W. Graham Medal in Computing Innovation. He also helped organize the first Selected Areas in Cryptography (SAC) workshop in 1994.
Van Oorschot received his Ph.D. in 1988 from the University of Waterloo. He was recognized (2016) as a Fellow of the Association for Computing Machinery.