William McIlhenny is a senior Wider Atlantic fellow at the German Marshall Fund of the United States. He was a senior policy advisor at the U.S. Department of State and director of policy, planning, and coordination for the Western Hemisphere bureau. Earlier, as a member of the secretary of state’s Policy Planning Staff, he focused on strategic dimensions of U.S. policy in Latin America and global futures.

At the White House, as director for North American affairs on the National Security Council staff, he managed interagency coordination of U.S. relations with Canada and Mexico. There he worked closely with the office of the newly created director of homeland security from 2001-02 to develop new frameworks for stronger border and other security cooperation that protects key economic and trade interests. 

As a career U.S. diplomat, he held a number of positions at U.S. missions in Latin America and Europe and had Washington-based assignments focused on UN Security Council issues, Congressional relations, and U.S.–Mexico relations. In Paris, he headed the U.S. Observation Mission to UNESCO, coordinating participation in its programs by multiple U.S. agencies.  

He is a periodic commentator on U.S. relations with Latin America and the region’s growing global integration. A member of the Pacific Council on International Policy, McIlhenny holds the Order of Merit of the Italian Republic and other civic and government awards and honors. He is a graduate of Georgetown University, served as an American Political Science Association fellow at SAIS, and completed other studies at the University of Tel Aviv.