Oliver Hart and Bengt Holmstrom have won the Nobel Memorial Prize in Economic Sciences for their contributions to contract theory. 
The Royal Swedish Academy of Sciences says their theories "are valuable to the understanding of real-life contracts and institutions, as well as potential pitfalls in contract design." Bengt Holmstrom was born in Finland, but has also been based in the US. He’s currently the Paul A. Samuelson Professor of Economics at Massachusetts Institute of Technology. 
Oliver Simon D'Arcy Hart is an economist and the Andrew E. Furer Professor of Economics at Harvard University.

Source: QNA