The U.S. Senate confirmed his nomination on August 6, 2004, and he was sworn in by Secretary Powell as ambassador on September 16, 2004.

After his return from Slovenia, he was the Dean of the Leadership and Management School of the Foreign Service Institute of the Department of State from 2007 until his retirement in 2010.

Between tours in Budapest, Ambassador Robertson served as the Law Enforcement Counselor at the American embassy in Moscow from 1995 to 1997.

Ambassador Robertson was the Director for Russian Affairs at the National Security Council from 2001 to 2002 when he returned to the Department of State to serve as a Career Development Officer in the Senior Level Division of the Bureau of Human Resources.

[1] Ambassador Robertson is retired and has served on a number of NGO boards, most recently for AFS-USA, a student exchange organization, from 2011 to 2017.