Source: US Department of State
Applicants must be US Citizens, at least 18 years old, have a 3.2+ GPA, be returning to their academic program upon completion of the internship, have at least 60 credit hours earned at time of application, and be able to work full-time during the 10-week internship in-person either in DC or assigned overseas post. Interns are paid $17.51 / hour.
If you are applying for a summer internship, the application is due in early November of the previous calendar year.