Many problems in Operations Research and the Management Sciences are concerned with the allocation of scarce resources. In a networked economy, such problems typically involve multiple decision makers. Economic mechanisms such as auctions and matching markets are being used to solve distributed resource allocation problems, and their design has been strongly influenced by techniques from Operations Research and the Management Sciences. Market design is a field at the intersection of OR/MS and Microeconomics and it considers properties of market mechanisms including allocative efficiency, stability, fairness, strategic and computational complexity. It brings together theoretical, empirical, and experimental methods, with an aim of studying relevant tradeoffs for policy makers and managers. Applications include spectrum auctions, procurement auctions, energy markets, or digital advertising markets.