[1] He attended St. Peter's Preparatory School in Jersey City, New Jersey, and received a bachelor's degree in history, magna cum laude, from Harvard University, and bachelor's and master's degrees in philosophy, politics and economics from Oxford University, England.

He held foreign assignments in Poland, India, the Soviet Union, Russia, Ukraine and in Belarus.

His Washington assignments include Deputy Assistant Secretary for the Bureau of South and Central Asian Affairs, Director of the Office of Russian Affairs (1997–1999) and Special Assistant to the Ambassador-at-Large for the New Independent States (1995–1997).

Krol taught at the National War College and was a member of the State Department's Senior Seminar.

He received several State Department Superior and Meritorious Honor awards.