Andrew Sommese is the Vincent J. and Annamarie Micus Duncan Professor in Mathematics, and is part of the Department of Applied and Computational Mathematics and Statistics. His current research centers on using algorithms for the numerical solution of systems of polynomials to numerically solve free boundary problems for systems of differential equations arising in tumor growth models. He has been working with a number of researchers to develop the fundamental algorithms of numerical algebraic geometry, a new subject whose goal is to compute and numerically manipulate the solution sets of polynomial systems, including the positive dimensional components of the solution sets. His group has developed a major software package, Bertini, to carry out these computations.