10 U.S.C. § 664 — Length of joint duty assignments

(a) General rule. A joint duty assignment must last at least two years. (b) Waiver authority. The Secretary of Defense may waive subsection (a) for an officer. (c) Exclusions from tour length. The Secretary may exclude from the two-year requirement: (1) service in an assignment that the officer did not complete because of (A) retirement, (B) release from active duty, (C) suspension under section 155(f)(2) or 164(g), or (D) a qualifying reassignment prescribed by Secretary regulations; and (2) service in an assignment that brings the officer’s accrued service for subsection (d)(2) to the subsection (a) requirement. (d) Full tour. An officer is considered to have completed a full tour upon completing: (1) an assignment meeting the two-year requirement; (2) accrued joint experience described in (e); (3) an assignment for which the Secretary granted a waiver under (b), if the Secretary decides the completed service counts as a full tour; or (4) a second or later assignment shorter than the required period. (e) Accrued joint experience. By regulation and with advice from the Chairman of the Joint Chiefs of Staff, the Secretary may identify joint experience that can be combined to equal a full tour, including temporary joint duty, joint individual training, and participation in joint exercises. (f) Constructive credit. For an officer other than a general or flag officer who is reassigned for military necessity within 60 days before meeting the tour-length criteria in (d)(1), the Secretary may credit enough constructive service to complete the applicable requirement, but no more than 60 days.