The dynamic kinetic resolution of alpha-keto esters via asymmetric transfer hydrogenation has been developed as a technique for the highly stereoselective construction of structurally diverse beta-substituted-alpha-hydroxy carboxylic acid derivatives. Through the development of a privileged m-terphenylsulfonamide for (arene)RuCl(monosulfonamide) complexes with a high affinity for selective alpha-keto ester reduction, excellent levels of chemo-, diastereo-, and enantiocontrol can be realized in the reduction of beta-aryl- and beta-chloro-alpha-keto esters.