[2] Before beginning his career at the State Department, Kelly taught Russian at Columbia University, where he also received his doctorate in Slavic Languages and Literatures in 1986.

[2] After joining the Foreign Service, he served in a variety of positions, including the Director of the Information Center in Belgrade, Yugoslavia from 1990 to 1992, and Assistant Cultural Affairs Officer in Leningrad and Moscow, U.S.S.R. from 1987 to 1990.

In August 2007, Kelly was appointed Director of the Office of Russian Affairs in Washington D.C., where he was responsible for managing the development and implementation of U.S. policy towards Russia.

On November 30, 2009, President Barack Obama announced his intent to nominate Kelly to be U.S. Representative to the Organization for Security and Cooperation in Europe, with the rank of Ambassador.

[6] After retirement from diplomatic service, Ambassador Kelly began teaching in the Departments of International Studies and Slavic Literatures at Northwestern University in April 2018.