John William Hatfield is an Associate Professor in the McCombs School of Business at the University of Texas at Austin. He studies market design--an engineering-oriented field of economic theory that considers how the design of the rules and regulations of a market affects the functioning and outcomes of that market. In particular, he studies matching theory, a field of economics that studies markets in which agents have explicit preferences over whom they buy from and sell to, not just over the underlying goods bought and sold.