The trade seminar is organized by the Paris school of economics, with additional funding from INRA and Sciences Po’. The seminar takes place every two weeks on Tuesday, 2 pm to 3.30pm, rotating by semesters between the three campus. In 2009-2010, the seminar’s venue is campus Paris Jourdan (48 bd Jourdan, 75014 Paris) between October 2009 and January 2010 and Maison des Sciences Economiques at University of Paris-I (106, boulevard de l'Hôpital, 75013 Paris) between February and June 2010. The seminar presents work in progress, by French and foreign scholars. Speakers meet PhD students and researchers during their visit on the campus. The seminar is organized by L.Fontagné, T. Mayer, A. Suwa-Eisenmann, T. Verdier, with the administrative help of B. Havet.