Tjalling C. Koopmans was a Dutch American economist and mathematician who, along with economist Leonid Kantorovich, was the joint recipient of the 1975 Nobel Memorial Prize in Economic Sciences. The duo won the award for their contributions to the theory of optimum allocation of resources. Though a graduate in mathematics and physics, Tjalling C. Koopmans grew interested in economics under the influence of economist, Jan Tinbergen, and subsequently earned a PhD in Economics from the University of Leiden. In 1940, he moved to USA, where he worked as a statistician with British Merchant Shipping Mission and thereby got the opportunity to devise models that reorganize shipping routes along with reducing associated costs and achieving results. As part of his research, he developed a rational method called as ‘Activity Analysis’. He was also one among the first persons to invent linear programming during his period. Later, he was part of the Cowles Commission at the University of Chicago between 1944 and 1955 and with the shifting of the Cowles Foundation to Yale University, he became a professor of economics at the University. He retired from the Yale University in 1981. He also served as the president of the American Economic Association in 1981.