Lance Fortnow is a professor in Computer Science at the Illinois Institute of Technology and a visiting fellow at Magdalen College, Oxford for Hilary Term 2026. He was the founding dean of the College of Computing at Illinois Tech, serving from June 2019 to June 2025.
Fortnow received his Ph.D. in Applied Mathematics at MIT in 1989 under the supervision of Michael Sipser. Before joining Illinois Tech, he was chair of the School of Computer Science at the Georgia Institute of Technology and previously a professor at Northwestern University and the University of Chicago, a senior research scientist at the NEC Research Institute, and a one-year visitor at CWI and the University of Amsterdam. He also held an adjunct professorship at the Toyota Technological Institute at Chicago from 2007 to 2018.
Fortnow's research spans computational complexity and its applications. His work on interactive proof systems and time-space lower bounds for satisfiability has led to his election as a 2007 ACM Fellow. In addition, he was an NSF Presidential Faculty Fellow from 1992–1998 and a Fulbright Scholar to the Netherlands in 1996–97. His current research focuses on how artificial intelligence changes the way we think about both the theory and applications of computing.
Among his many activities, Fortnow served as the founding editor-in-chief of the ACM Transactions on Computation Theory, as chair of ACM SIGACT, and on the Computing Research Association board of directors. He chaired the IEEE Conference on Computational Complexity from 2000 to 2006. Fortnow founded and co-authors the Computational Complexity weblog, the first major theoretical computer science blog, which has run continuously since 2002.
Fortnow's survey The Status of the P versus NP Problem is one of the CACM's most downloaded articles. He wrote a popular science book, The Golden Ticket: P, NP and the Search for the Impossible, loosely based on that article.