Second, and perhaps more importantly, the Mexicans implemented the methodological idea of conducting controlled experiments to find out which policies work and which don’t work in developing countries (which has fed into the exciting Randomized Control Trials movement in the field of development economics). Also in the 1990’s, largely thanks to the leadership of then-President Ernesto Zedillo, Mexico adopted non-partisan federal electoral institutions that in 2006 proved able to resolve successfully a disputed election.