Foreign Service officer

They spend most of their careers overseas as members of U.S. embassies, consulates, and other diplomatic missions, though some receive assignments to serve at combatant commands, Congress, and educational institutions such as the various U.S. service academies.

In the early twenty-first century, about two-thirds of U.S. ambassadors have been career Foreign Service members primarily drawn from the Department of State.

Applicants for State Department FSO jobs go through a highly competitive written exam, oral assessment, and security investigation process before they are eligible to be hired.

These limited appointees are not officially members of Foreign Service and must leave anytime a career officer becomes available for their positions.

Because USAID has a strong technical focus in many of its overseas positions, FSOs are generally recruited for specific backstops.