10 U.S.C. § 4251 (ARMED FORCES)
§ 4251. Major defense acquisition programs: factors to be considered before Milestone A approval
(a) Responsibilities.—
Before granting Milestone A approval for a major defense acquisition program or a major subprogram, the milestone decision authority for the program or subprogram shall ensure that—
(1) information about the program or subprogram is sufficient to warrant entry of the program or subprogram into the risk reduction phase;
(2) the cost, schedule, technical feasibility, and performance trade-offs that have been made with regard to the program do not overly constrain future trade space; and
(3) there are sound plans for progression of the program or subprogram to the development phase.
(b) Factors to Be Considered for Milestone a Approval.—
A major defense acquisition program or subprogram may not receive Milestone A approval or otherwise be initiated prior to Milestone B approval until the milestone decision authority confirms that the following factors were considered in the decision to grant Milestone A approval:
(1) The program or subprogram fulfills an approved requirements document.
(2) The program or subprogram has conducted appropriate market research.
(3) With respect to any identified areas of risk, there is a plan to reduce the risk.
(4) Planning for sustainment has been addressed.
(5) An analysis of alternatives has been performed consistent with study guidance developed by the Director of Cost Assessment and Program Evaluation, or in lieu of an analysis of alternatives, early experimentation with a combatant commander has been conducted.
(6) A life cycle cost estimate for the program or subprogram has been submitted by the component and that the level of resources required to complete the technology maturation and risk reduction phase of the program is sufficient for successful program execution.
(7) The program or subprogram meets any other considerations the milestone decision authority considers relevant.
(c) Written Record of a Milestone Decision.—
The milestone decision authority shall issue a written record of a milestone decision at the time that Milestone A approval is granted. The record shall confirm compliance with subsection (b) and specifically state that the milestone decision authority considered the factors described in such subsection prior to the decision to grant milestone approval. The milestone decision authority shall retain records of the basis for the milestone decision.
(d) Submissions to Congress on Milestone A.—
(1) Notification.—
Not later than 15 days after granting Milestone A approval for a major defense acquisition program, the milestone decision authority for the program shall provide to the congressional defense committees and, in the case of intelligence or intelligence-related activities, the congressional intelligence committees a written record of the milestone decision.
(2) Additional information.—
At the request of any of the congressional defense committees or, in the case of intelligence or intelligence-related activities, the congressional intelligence committees, the milestone decision authority shall submit to the committee an explanation of the basis for the decision to grant Milestone A approval with respect to a major defense acquisition program or major subprogram, and make available all underlying documentation.
(e) Definitions.—
In this section:
(1) The term “requirements document” means any capabilities requirement document that establishes the need for a materiel approach to resolve a capability gap.
(2) The term “Milestone A approval” means a decision to enter into technology maturation and risk reduction pursuant to guidance prescribed by the Secretary of Defense for the management of Department of Defense acquisition programs.
(3) The term “Milestone B approval” has the meaning provided that term in section 4172(e)(7) of this title.
(4) The term “milestone decision authority”, with respect to a major defense acquisition program or a major subprogram, means the official within the Department of Defense designated with the overall responsibility and authority for acquisition decisions for the program or subprogram, including authority to approve entry of the program or subprogram into the next phase of the acquisition process.
(5) The term “congressional intelligence committees” has the meaning given that term in section 437(c) of this title.
(Added Pub. L. 110–181, div. A, title IX, § 943(a)(1), Jan. 28, 2008, 122 Stat. 288, § 2366b; renumbered § 2366a and amended Pub. L. 110–417, [div. A], title VIII, § 813(b), (e)(1), Oct. 14, 2008, 122 Stat. 4527; Pub. L. 111–23, title I, § 101(d)(3), title II, §§ 201(e), 204(a), (b), May 22, 2009, 123 Stat. 1710, 1720, 1723; Pub. L. 111–383, div. A, title VIII, § 814(b), title X, § 1075(b)(33), Jan. 7, 2011, 124 Stat. 4266, 4370; Pub. L. 112–81, div. A, title VIII, § 801(a), (e)(1), Dec. 31, 2011, 125 Stat. 1482, 1483; Pub. L. 112–239, div. A, title III, § 322(e)(1), title X, § 1076(a)(10), Jan. 2, 2013, 126 Stat. 1695, 1948; Pub. L. 114–92, div. A, title VIII, § 823(a), Nov. 25, 2015, 129 Stat. 902; Pub. L. 114–328, div. A, title VIII, §§ 806(b), 807(d), 808(a), Dec. 23, 2016, 130 Stat. 2259, 2262; Pub. L. 115–232, div. A, title VIII, § 831(b)(2), Aug. 13, 2018, 132 Stat. 1857; Pub. L. 116–92, div. A, title XVII, § 1731(a)(44), Dec. 20, 2019, 133 Stat. 1814; renumbered § 4251 and amended Pub. L. 116–283, div. A, title XVIII, § 1847(d)(1), Jan. 1, 2021, 134 Stat. 4254; Pub. L. 118–159, div. A, title VIII, § 806(a)(1), Dec. 23, 2024, 138 Stat. 1972; Pub. L. 119–60, div. A, title XVIII, § 1811(g)(2), Dec. 18, 2025, 139 Stat. 1243.)
heading: Editorial Notes
heading: Amendments
text: 2025—Subsec. (e)(1). Pub. L. 119–60 struck out “approved by the Joint Requirements Oversight Council” after “capabilities requirement document”.
2024—Pub. L. 118–159, § 806(a)(1)(A), substituted “factors to be considered” for “determination required” in section catchline.
Subsec. (a)(2). Pub. L. 118–159, § 806(a)(1)(B)(ii), inserted “do not overly constrain future trade space” after “with regard to the program”.
Pub. L. 118–159, § 806(a)(1)(B)(i), which directed striking out “the Secretary of the military department concerned and the Chief of the armed forces concerned concur in”, was executed by striking out “the Secretary of the military department concerned and the Chief of the armed force concerned concur in” before “the cost”, to reflect the probable intent of Congress.
Subsec. (b). Pub. L. 118–159, § 806(a)(1)(C), amended subsec. (b) generally. Prior to amendment, subsec. (b) related to written determination requirements for approval.
Subsec. (c). Pub. L. 118–159, § 806(a)(1)(E), added subsec. (c). Former subsec. (c) redesignated (d).
Subsec. (d). Pub. L. 118–159, § 806(a)(1)(D), redesignated subsec. (c) as (d). Former subsec. (d) redesignated (e).
Subsec. (d)(1). Pub. L. 118–159, § 806(a)(1)(F)(i)(II), substituted “a written record of the milestone decision.” for “a brief summary report that contains the following elements:” and struck out subpars. (A) to (G) which listed elements to be included in the brief summary report required for Milestone A approval.
Pub. L. 118–159, § 806(a)(1)(F)(i)(I), which directed substitution of “notification” for “brief summary report” in heading, was executed by substituting “Notification” for “Brief summary report”, to reflect the probable intent of Congress.
Subsec. (d)(2). Pub. L. 118–159, § 806(a)(1)(F)(ii), amended par. (2) generally. Prior to amendment, par. (2) related to requests for additional explanation of the basis for a determination.
Subsec. (e). Pub. L. 118–159, § 806(a)(1)(D), (G), redesignated subsec. (d) as (e) and substituted “requirements document” for “initial capabilities document” in par. (1), redesignated pars. (5) and (8) as (4) and (5), respectively, and struck out former pars. (4), (6), and (7) which defined core logistics capabilities, fielding target, and major system component, respectively.
2021—Pub. L. 116–283, § 1847(d)(1)(A), renumbered section 2366a of this title as this section.
Subsec. (b)(4). Pub. L. 116–283, § 1847(d)(1)(B)(i), substituted “section 4272(a)(1)” for “section 2448b(a)(1)”.
Subsec. (b)(8). Pub. L. 116–283, § 1847(d)(1)(B)(ii), substituted “subchapter II of chapter 327” for “subchapter II of chapter 144B”.
Subsec. (c)(1)(A). Pub. L. 116–283, § 1847(d)(1)(C)(i), substituted “section 4271(a)” for “section 2448a(a)”.
Subsec. (c)(1)(C). Pub. L. 116–283, § 1847(d)(1)(C)(ii), substituted “section 3221(b)(6)” for “section 2334(a)(6)”.
Subsec. (c)(1)(E). Pub. L. 116–283, § 1847(d)(1)(C)(iii), substituted “section 4272” for “section 2448b”.
Subsec. (d)(1), (2). Pub. L. 116–283, § 1847(d)(1)(D)(i), redesignated pars. (2) and (3) as (1) and (2), respectively, and struck out former par. (1) which defined “major defense acquisition program”.
Subsec. (d)(3). Pub. L. 116–283, § 1847(d)(1)(D)(ii), substituted “section 4172(e)(7)” for “section 2366(e)(7)”.
Pub. L. 116–283, § 1847(d)(1)(D)(i), redesignated par. (4) as (3). Former par. (3) redesignated (2).
Subsec. (d)(4), (5). Pub. L. 116–283, § 1847(d)(1)(D)(i), redesignated pars. (5) and (7) as (4) and (5), respectively. Former par. (4) redesignated (3).
Subsec. (d)(6). Pub. L. 116–283, § 1847(d)(1)(D)(iii), substituted “section 4271(a)” for “section 2448a(a)”.
Pub. L. 116–283, § 1847(d)(1)(D)(i), redesignated par. (8) as (6) and struck out former par. (6) which defined “major subprogram”.
Subsec. (d)(7). Pub. L. 116–283, § 1847(d)(1)(D)(iv), substituted “section 4401(b)(3)” for “section 2446a(b)(3)”.
Pub. L. 116–283, § 1847(d)(1)(D)(i), redesignated par. (9) as (7). Former par. (7) redesignated (5).
Subsec. (d)(8) to (10). Pub. L. 116–283, § 1847(d)(1)(D)(i), redesignated pars. (8) to (10) as (6) to (8), respectively.
2019—Subsec. (c)(1)(F). Pub. L. 116–92 substituted “subsection (b)(6)” for “section 2366a(b)(6) of this title”.
2018—Subsec. (c)(1)(A). Pub. L. 115–232 struck out “by the Secretary of Defense” after “established”.
2016—Subsec. (b)(4). Pub. L. 114–328, § 807(d), inserted “, including risks determined by the identification of critical technologies required under section 2448b(a)(1) of this title or any other risk assessment” after “areas of risk”.
Subsec. (b)(8), (9). Pub. L. 114–328, § 806(b), added par. (8) and redesignated former par. (8) as (9).
Subsec. (c). Pub. L. 114–328, § 808(a)(1), amended subsec. (c) generally. Prior to amendment, text of subsec. (c) read as follows: “At the request of any of the congressional defense committees, the Secretary of Defense shall submit to the committee an explanation of the basis for a determination made under subsection (b) with respect to a major defense acquisition program, together with a copy of the written determination. The explanation shall be submitted in unclassified form, but may include a classified annex.”
Subsec. (d)(8) to (10). Pub. L. 114–328, § 808(a)(2), added pars. (8) to (10).
2015—Pub. L. 114–92 amended section generally. Prior to amendment, section related to certification required before Milestone A approval of major defense acquisition programs.
2013—Pub. L. 112–239, § 1076(a)(10)(C), made technical amendment to directory language of Pub. L. 112–81, § 801(e)(1)(A). See 2011 Amendment note below.
Subsec. (a)(4). Pub. L. 112–239, § 322(e)(1), substituted “core logistics capabilities” for “core depot-level maintenance and repair capabilities”.
Subsec. (a)(5), (6). Pub. L. 112–239, § 1076(a)(10)(A), made technical amendment to directory language of Pub. L. 112–81, § 801(a)(1)(B). See 2011 Amendment notes below.
Subsec. (c)(7). Pub. L. 112–239, § 1076(a)(10)(B), made technical amendment to directory language of Pub. L. 112–81, § 801(a)(2). See 2011 Amendment note below.
Pub. L. 112–239, § 322(e)(1), substituted “core logistics capabilities” for “core depot-level maintenance and repair capabilities” in two places.
2011—Pub. L. 112–81, § 801(e)(1)(A), as amended by Pub. L. 112–239, § 1076(a)(10)(C), struck out “or Key Decision Point A” after “Milestone A” in section catchline.
Subsec. (a). Pub. L. 112–81, § 801(e)(1)(B), struck out “, or Key Decision Point A approval in the case of a space program,” after “Milestone A approval” and “, or Key Decision Point B approval in the case of a space program,” after “Milestone B approval” in introductory provisions.
Subsec. (a)(2). Pub. L. 112–81, § 801(a)(1)(A), substituted “function” for “core competency”.
Subsec. (a)(4). Pub. L. 112–81, § 801(a)(1)(C), added par. (4). Former par. (4) redesignated (5).
Subsec. (a)(5). Pub. L. 112–81, § 801(a)(1)(B), as amended by Pub. L. 112–239, § 1076(a)(10)(A), redesignated par. (4) as (5). Former par. (5) redesignated (6).
Subsec. (a)(6). Pub. L. 112–81, § 801(a)(1)(D), substituted “develop, procure, and sustain” for “develop and procure”.
Pub. L. 112–81, § 801(a)(1)(B), as amended by Pub. L. 112–239, § 1076(a)(10)(A), redesignated par. (5) as (6).
Subsec. (b)(1). Pub. L. 112–81, § 801(e)(1)(C)(i), struck out “(or Key Decision Point A approval in the case of a space program)” after “Milestone A approval”.
Pub. L. 111–383, § 814(b)(1)(A), substituted “a major defense acquisition program certified by the Milestone Decision Authority under subsection (a) or a designated major subprogram of such program, if the projected cost of the program or subprogram” for “a major defense acquisition program certified by the Milestone Decision Authority under subsection (a), if the projected cost of the program”.
Subsec. (b)(2). Pub. L. 111–383, § 814(b)(1)(B), inserted “or designated major subprogram” after “major defense acquisition program”.
Subsec. (b)(2)(C)(ii). Pub. L. 112–81, § 801(e)(1)(C)(ii), struck out “, or Key Decision Point A approval in the case of a space program,” after “Milestone A approval”.
Subsec. (c). Pub. L. 111–383, § 1075(b)(33)(A), inserted a space after “(c)”.
Subsec. (c)(2) to (5). Pub. L. 111–383, § 814(b)(2), added par. (2) and redesignated former pars. (2) to (4) as (3) to (5), respectively. Former par. (5) redesignated (6).
Pub. L. 111–383, § 1075(b)(33)(B), which directed substitution of “section 118b(c)(3) of this title” for “section 125a(a) of this title” in par. (4), was executed by making the substitution in par. (5) to reflect the probable intent of Congress and the amendment by Pub. L. 111–383, § 814(b)(2)(A). See above.
Subsec. (c)(6). Pub. L. 111–383, § 814(b)(2)(A), redesignated par. (5) as (6).
Subsec. (c)(7). Pub. L. 112–81, § 801(a)(2), as amended by Pub. L. 112–239, § 1076(a)(10)(B), added par. (7).
2009—Subsec. (a). Pub. L. 111–23, § 204(a), substituted “may not receive Milestone A approval, or Key Decision Point A approval in the case of a space program, or otherwise be initiated prior to Milestone B approval, or Key Decision Point B approval in the case of a space program,” for “may not receive Milestone A approval, or Key Decision Point A approval in the case of a space program,” in introductory provisions.
Subsec. (a)(3). Pub. L. 111–23, § 201(e)(1), struck out “and” at end.
Subsec. (a)(4). Pub. L. 111–23, § 201(e)(3), added par. (4). Former par. (4) redesignated (5).
Pub. L. 111–23, § 101(d)(3), inserted “, with the concurrence of the Director of Cost Assessment and Program Evaluation,” after “has been submitted”.
Subsec. (a)(5). Pub. L. 111–23, § 201(e)(2), redesignated par. (4) as (5).
Subsec. (b). Pub. L. 111–23, § 204(b), designated existing provisions as par. (1), substituted “by at least 25 percent, or the program manager determines that the period of time required for the delivery of an initial operational capability is likely to exceed the schedule objective established pursuant to section 181(b)(5) of this title by more than 25 percent,” for “by at least 25 percent,”, and added par. (2).
2008—Pub. L. 110–417, § 813(b), renumbered section 2366b of this title as this section.
Subsec. (a)(1), (2). Pub. L. 110–417, § 813(e)(1)(A), substituted “program” for “system”.
Subsec. (a)(3). Pub. L. 110–417, § 813(e)(1)(B), substituted “if the program” for “if the system” and “such program” for “such system”.
Subsec. (a)(4). Pub. L. 110–417, § 813(e)(1)(A), substituted “program” for “system” in two places.
Subsec. (b). Pub. L. 110–417, § 813(e)(1)(C), substituted “major defense acquisition program” for “major system”, “cost of the program” for “cost of the system”, “estimate for the program” for “estimate for the system”, “the program concerned” for “the system concerned”, and “procure the program” for “procure the system”.
Subsec. (c)(1). Pub. L. 110–417, § 813(e)(1)(D), substituted “ ‘major defense acquisition program’ ” for “ ‘major system’ ” and “2430” for “2302(5)”.
heading: Statutory Notes and Related Subsidiaries
heading: Effective Date of 2021 Amendment
text: Amendment by Pub. L. 116–283 effective Jan. 1, 2022, with additional provisions for delayed implementation and applicability of existing law, see section 1801(d) of Pub. L. 116–283, set out as a note preceding section 3001 of this title.
heading: Effective Date of 2013 Amendment
text: Pub. L. 112–239, div. A, title III, § 322(f), Jan. 2, 2013, 126 Stat. 1695, provided that: “This section [enacting sections 2460 and 2464 of this title, amending this section and sections 2366b, 2460, and 2464 of this title, repealing sections 2460 and 2464 of this title, and amending provisions set out as a note under this section] and the amendments made by this section shall take effect on December 31, 2011, the date of the enactment of the National Defense Authorization Act for Fiscal Year 2012 [Pub. L. 112–81], immediately after the enactment of that Act.”
Pub. L. 112–239, div. A, title X, § 1076(a), Jan. 2, 2013, 126 Stat. 1947, provided that the amendment made by section 1076(a)(10) is effective Dec. 31, 2011, and as if included in Pub. L. 112–81 as enacted.
heading: Effective Date
text: Pub. L. 110–181, div. A, title IX, § 943(c), Jan. 28, 2008, 122 Stat. 289, as amended by Pub. L. 110–417, [div. A], title VIII, § 813(e)(2)(B), Oct. 14, 2008, 122 Stat. 4528, provided that: “Section 2366b of title 10, United States Code [now 10 U.S.C. 4251], as added by subsection (a), shall apply to major defense acquisition programs on and after March 1, 2008. In the case of the certification required by [former] paragraph (2) of subsection (a) of such section, during the period prior to the completion of the first quadrennial roles and missions review required by [former] section 118b of title 10, United States Code, the certification required by that paragraph shall be that the system is being executed by an entity with a relevant core competency as identified by the Secretary of Defense.”
heading: Analysis of Alternatives Pursuant to Materiel Development Decisions
text: Pub. L. 116–92, div. A, title VIII, § 832, Dec. 20, 2019, 133 Stat. 1493, provided that:
“(a) Timeline.—
Not later than 180 days after the date of the enactment of this Act [Dec. 20, 2019], the Secretary of Defense shall update existing guidance for analyses of alternatives conducted pursuant to a materiel development decision for a major defense acquisition program to incorporate the following:
“(1) Study completion within nine months.
“(2) Study guidance issued by the Director, Cost Assessment and Program Evaluation of a scope designed to provide for reasonable completion of the study within the nine-month period.
“(3) Procedures for waiver of the timeline requirements of this subsection on a case-by-case basis if—
“(A) the subject of the analysis is of extreme technical complexity;
“(B) collection of additional intelligence is required to inform the analysis;
“(C) insufficient technical expertise is available to complete the analysis; or
“(D) the Secretary determines that there [are] other sufficient reasons for delay of the analysis.
“(b) Reporting.—
If an analysis of alternatives cannot be completed within the allotted time, or a waiver is used, the Secretary shall report to the congressional defense committees [Committees on Armed Services and Appropriations of the Senate and the House of Representatives] the following information:
“(1) For a waiver, the basis for use of the waivers, including the reasons why the study cannot be completed within the allotted time.
“(2) For a study estimated to take more than nine months—
“(A) an estimate of when the analysis will be completed;
“(B) an estimate of any additional costs to complete the analysis; and
“(C) other relevant information pertaining to the analysis and its completion.
“(c) Report on Analyses of Alternatives.—
“(1) Assessment.—
“(A) In general.—
The Under Secretary of Defense for Acquisition and Sustainment shall engage with an independent entity, including under the Program for Acquisition Innovation Research, to assess the conduct of analyses of alternatives.
“(B) Elements.—
The assessment required under subparagraph (A) shall—
“(i) assess the time required to complete analyses of alternatives within the Department of Defense completed over the last five fiscal years, as compared with best practices;
“(ii) provide recommendations and policy options to improve analyses of alternatives; and
“(iii) discuss any other matters as identified by the Under Secretary.
“(C) Access to data.—
The Under Secretary shall ensure that the independent entity is provided access to the data, information, and resources necessary to complete the required analyses and assessment.
“(2) Report.—
Not later than one year after the date of the enactment of this Act, the Under Secretary shall submit to the congressional defense committees a report including the assessment required under paragraph (1) and a review and assessment by the Under Secretary of the findings made in the assessment.”
heading: Milestone A Decisions
text: Pub. L. 114–92, div. A, title VIII, § 802(d)(2), Nov. 25, 2015, 129 Stat. 880, which required the Chief of the Armed Force concerned to provide the Chief’s views on cost, schedule, technical feasibility, and performance trade-offs to the milestone decision authority for a major defense acquisition program prior to a Milestone A decision, was repealed by Pub. L. 119–60, div. A, title VIII, § 811(b)(8)(A), Dec. 18, 2025, 139 Stat. 948.
heading: Guidance
text: Pub. L. 112–81, div. A, title VIII, § 801(d), Dec. 31, 2011, 125 Stat. 1483, provided that: “Not later than 120 days after the date of the enactment of this Act [Dec. 31, 2011], the Secretary of Defense shall issue guidance implementing the amendments made by subsections (a) and (b) [amending this section and section 2366b of this title], and subsection (c) [set out as a note preceding section 4321 of this title], in a manner that is consistent across the Department of Defense.”