James Renegar is a Professor in the School of Operations Research and Information Engineering at Cornell University, where he has been since 1987, after receiving his PhD in Mathematics from UC Berkeley, under the guidance of Steve Smale. Throughout his career, Renegar's research has focused on algorithms—especially on their theory—including, interior-point methods for convex optimization (for which he wrote a well-known introductory monograph), quantifier elimination methods for the first-order theory of the reals, development of the notion of "condition number" in the context of general conic optimization problems, algorithms for hyperbolic programming, and most recently, the discovery of a simple paradigm for solving general convex conic optimization problems by first-order methods.

In 1995, Renegar was one of the five founding members of the Society for Foundations of Computational Mathematics. He long served on its board of directors, and has also served in a multitude of other capacities, including his current role as associate editor for the Society's journal.