Lasso served as Governor of the Guayas Province from 1998 through 1999. He was appointed by President Jamil Mahuad to serve as Superminister of Economy and Energy, a position he served from August through September 1999. In 2003, President Lucio Gutiérrez appointed Lasso to serve as Itinerant Ambassador, a position he served for only a few months in the same year.