22 U.S.C. § 3949

1. (a)A limited appointment in the Service, including an appointment of an individual who is an employee of an agency, may not exceed 5 years in duration and, except as provided in subsections (b) and (c), may not be extended or renewed. A limited appointment in the Service which is limited by its terms to a period of one year or less is a temporary appointment.
2. (b)A limited appointment may be extended for continued service—
   1. (1)as a consular agent;
   2. (2)in accordance with section 3951(a) of this title;
   3. (3)as a career candidate, if—
      1. (A)continued service is determined appropriate to remedy a matter that would be cognizable as a grievance under subchapter XI; or
      2. (B)the individual is serving in the uniformed services (as defined in section 4303 of title 38) and the limited appointment expires in the course of such service;
   4. (4)as a career employee in another Federal personnel system serving in a Foreign Service position on detail from another agency;
   5. (5)as a foreign national employee;
   6. (6)in exceptional circumstances if the Secretary determines the needs of the Service require the extension of—
      1. (A)a limited noncareer appointment for a period not to exceed 1 year; or
      2. (B)a limited appointment of a career candidate for the minimum time needed to resolve a grievance, claim, investigation, or complaint not otherwise provided for in this section.
3. (c)
   1. (1)Except as provided in paragraph (2) noncareer employees who have served for 5 consecutive years under a limited appointment under this section may be reappointed to a subsequent noncareer limited appointment if there is at least a 1-year break in service before such new appointment.
   2. (2)The Secretary may waive the 1-year break requirement under paragraph (1) in cases of special need.