Christopher Landau was sworn in as the 23rd Deputy Secretary of State on March 25, 2025. Deputy Secretary Landau served as United States Ambassador to Mexico from 2019 to 2021 during President Trump’s first administration. Before and after his tenure in Mexico, he was engaged in the private practice of law in Washington, D.C. for more than three decades.

As Ambassador to Mexico, Deputy Secretary Landau presided over the United States’ largest diplomatic mission and fostered unprecedented bilateral cooperation that yielded results including the ratification and entry into force of the U.S.-Mexico-Canada Free Trade Agreement, protection of border commerce and regional supply chains during the pandemic, and the lowest levels of illegal migration in years.

Deputy Secretary Landau’s legal practice focused on appellate litigation. He has briefed and argued cases involving a wide variety of topics in the U.S. Supreme Court and all of the federal courts of appeals.

Deputy Secretary Landau was born in Madrid, Spain, where his father George Landau (later United States Ambassador to Paraguay, Chile, and Venezuela) was stationed with the U.S. Foreign Service. Deputy Secretary Landau brings his perspective as both a recent United States Ambassador and upbringing in the foreign service, as well as his extensive legal background, to his current position.

A graduate of Harvard College and Harvard Law School, Deputy Secretary Landau clerked twice at the Supreme Court, first for Justice Antonin Scalia and then for Justice Clarence Thomas. He is fluent in Spanish and proficient in French. He is married to Caroline Bruce Landau, and they have two adult children, Nathaniel and Julia.