22 USC 2507 - Training program

(a) Applicants for enrollment and enrolled volunteers 
The President shall make provision for such training as he deems appropriate for each applicant for enrollment as a volunteer and each enrolled volunteer. All of the provisions of this chapter applicable respectively to volunteers and volunteer leaders shall be applicable to applicants for enrollment as such during any period of training occurring prior to enrollment, and the respective terms volunteers and volunteer leaders shall include such applicants during any such period of training.
(b) Citizen trainees for voluntary programs; foreign nationals as trainees; advances of funds or reimbursement basis; use of credits 
The President may also make provision, on the basis of advances of funds or reimbursement to the United States, for training for citizens of the United States, other than those referred to in subsection (a) of this section, who have been selected for service abroad in programs not carried out under authority of this chapter which are similar to those authorized by this chapter. The provisions of section 2508 of this title shall apply, on a similar advance of funds or a reimbursement basis, with respect to persons while within the United States for training under authority of this subsection. Advances or reimbursements received under this subsection may be credited to the current applicable appropriation, fund, or account and shall be available for the purposes for which such appropriation, fund, or account is authorized to be used.