sentences:  Téllez graduated from the "Instituto Tecnológico Autónomo de México" (ITAM) with a bachelor's degree in Economics "(summa cum laude)" took post graduate studies in Law at the National Autonomous University of Mexico (UNAM) and received a doctorate's degree in Economics from the Massachusetts Institute of Technology.He is a member of the Institutional Revolutionary Party (PRI) since 1980, where he headed the Institute for Economic, Social and Political Studies (IEPES).He joined the federal cabinet as Undersecretary of Planning at the Secretariat of Agriculture during the Carlos Salinas de Gortari administration, headed the Office of the Presidency in the Ernesto Zedillo administration and, from 1997 to 2000, served as his Secretary of Energy.