After completing his education at École Polytechnique and École des Ponts, and a PhD in mathematics from Paris-Dauphine University, Jean Tirole set off for the USA. He received a PhD from MIT, and then returned there in 1984 to teach economics. It was also around this time that he joined the Center for Education and Research on Socioeconomic Analysis (CERAS) of the École des Ponts. Jean Tirole went back to l’X to teach economics from 1994 to 1996. He relied on game theory to make a tremendous contribution to the theory of industrial organization, and conducted pivotal research on the theory of two-sided markets. In 2014, Tirole won the Nobel Prize in Economics for his work on industrial economics, namely his “analysis of market power and regulation”. This alum of École Polytechnique is the third French economist to receive the prestigious award.