Ambassador León has held numerous posts in academic, private and government circles. From 1989 to 1991, he worked as the technical manager at the Salvadoran Chamber of Commerce and Industry as well as adviser to the National Association for the Private Enterprise and the Coffee Processors and Exporters of El Salvador. He joined the Ministry of Economy in 1992 as director of international trade negotiations and economic integration, advancing to vice minister of economy in 1994.

Ambassador León dedicates much of his time to immigration issues and promoting Salvadoran business and trade opportunities abroad.