The source selection decision: what the record must show

The source selection decision is the choice, by the source selection authority (SSA), of the proposal that offers the best value to the Government in a negotiated competition. Section 15.308 of the Federal Acquisition Regulation (FAR) sets what the record must show. The decision must rest on a comparative assessment of proposals against all source selection criteria in the solicitation and represent the SSA's independent judgment. The documentation must give the rationale for any business judgments and tradeoffs, including benefits associated with additional costs. That documentation "need not quantify the tradeoffs." In the Department of Defense (DoD), the Source Selection Procedures dated August 20, 2022 add detail on how the decision document is written.

Two texts of Part 15

Two versions of Part 15 are in force. The codified FAR on Acquisition.gov is at Federal Acquisition Circular (FAC) 2026-01, effective March 13, 2026. The FAR Overhaul has published a rewritten Part 15 that agencies adopt by deviation. DoD's class deviation 2026-O0048, signed February 27, 2026, directs contracting officers to use the overhaul text, a revised Defense FAR Supplement (DFARS) Part 215, and revised DFARS Procedures, Guidance, and Information (PGI) from March 16, 2026, until it is rescinded or incorporated.

Rule	Codified FAR	Overhaul text used by DoD
Tradeoff approach	15.101-1	15.103-1
Lowest price technically acceptable	15.101-2	15.103-2
Proposal evaluation	15.305	15.202
Source selection decision	15.308	15.205

The decision rule reads nearly the same in both. The overhaul text adds a third approach at 15.103-3: award to the highest technically rated proposal with a fair and reasonable price, with no tradeoffs.

Tradeoff or lowest price technically acceptable

FAR 15.101 describes a best value continuum. When the requirement is clearly definable and performance risk is minimal, cost or price may dominate. The less definitive the requirement, the more technical or past performance considerations may dominate.

Under a tradeoff, FAR 15.101-1 lets the Government award to other than the lowest priced offeror. The solicitation must state whether all non-cost factors, combined, are significantly more important than, approximately equal to, or significantly less important than cost or price. The perceived benefits of the higher priced proposal must merit the additional cost.

The lowest price technically acceptable (LPTA) approach permits no tradeoffs. For DoD, the deviation's DFARS 215.103-270 limits it to cases that meet eight conditions. Among them, the contract file must contain a determination that the lowest price reflects full life-cycle costs, and the contracting officer must document the circumstances that justify LPTA. DoD must avoid LPTA, to the maximum extent practicable, for information technology services, cybersecurity services, and other knowledge-based professional services.

What the evaluation record contains

FAR 15.305 requires evaluation solely on the factors in the solicitation and allows any rating method, including color or adjectival ratings, numerical weights, and ordinal rankings. The relative strengths, deficiencies, significant weaknesses, and risks must be documented in the contract file, and the contracting officer documents the cost or price evaluation. When tradeoffs are performed, the record includes an assessment of each offeror's ability to accomplish the technical requirements and a summary, matrix, or quantitative ranking with supporting narrative. The overhaul's 15.202 keeps the strengths, weaknesses, and risks but drops the summary-matrix language.

The DoD procedures apply to major system acquisitions and to competitive Part 15 acquisitions above $10 million. At $100 million or more, the SSA must be someone other than the procuring contracting officer, and a Source Selection Advisory Council (SSAC) is required. Technical ratings use five colors: Blue (Outstanding), Purple (Good), Green (Acceptable), Yellow (Marginal), and Red (Unacceptable). The minimum file includes the Source Selection Evaluation Board reports, any SSAC comparative analysis, and the Source Selection Decision Document (SSDD).

The decision document

The procedures require an SSDD for all source selections, as the single summary document supporting the choice. The SSA must not rely on adjectival ratings alone and is not bound by the evaluators' findings if the SSA has a rational basis for a different view. If a higher priced offer is selected, the SSDD must say why the price is justified; if a superior technical proposal is not selected, it must say why. Each tradeoff states the benefits expected, their value, and why paying more is in the Government's interest. In an LPTA, the SSDD contains no comparative analysis.

The SSDD can be released, redacted, at a debriefing. The 2022 procedures give a small business option for awards of $10 million to $100 million and disclosure above $100 million. The 2026 deviation's DFARS 215.301-170 uses $15 million to $150 million, extends the option to nontraditional defense contractors, and sets disclosure above $150 million.

The pointer to the procedures has moved too. Codified PGI 215.300 links the August 20, 2022 memorandum; the deviation's PGI 215.200 points to the same document.

What to check

• Which Part 15 text governs the solicitation, codified or overhaul, and do its section citations match that text?
• Does the solicitation state the relative importance of non-cost factors combined against price?
• Does the SSDD compare proposals against every stated criterion, or only repeat adjectival ratings?
• If the chosen proposal was not the lowest priced, does the SSDD state the benefits and why they merit the premium?
• For a DoD LPTA award, does the file hold the life-cycle cost determination and the written justification?
• Were the 2026 debriefing thresholds applied, rather than the 2022 figures?

Azcuna's LEDGER turns a trade study into a Decision Package in which every number cites its source and AI agents draft but never decide. It was proposed to the Army under SBIR Phase I topic ARM26BX06-NV012, and the proposal was submitted on October 21, 2026.

Sources

1. 1FAR 15.308 Source selection decision · Acquisition.gov, FAC 2026-01, effective March 13, 2026
2. 2FAR 15.305 Proposal evaluation · Acquisition.gov, FAC 2026-01, effective March 13, 2026
3. 3FAR 15.101 Best value continuum · Acquisition.gov, FAC 2026-01, effective March 13, 2026
4. 4FAR 15.101-1 Tradeoff process · Acquisition.gov, FAC 2026-01, effective March 13, 2026
5. 5FAR Overhaul - Part 15 · Acquisition.gov, FAR Overhaul
6. 6Class Deviation - Revolutionary Federal Acquisition Regulation (FAR) Overhaul Part 15, Defense FAR Supplement (DFARS) Part 215 (DARS Tracking Number 2026-O0048) · Defense Pricing, Contracting, and Acquisition Policy, effective March 16, 2026
7. 7Department of Defense Source Selection Procedures · Defense Pricing and Contracting, August 20, 2022
8. 8PGI 215.3 - Source Selection · Acquisition.gov, DFARS PGI Change 5/7/2026

Where this shows up in our work

• LEDGER, auditable Army acquisition decisions turns a trade study into a package where every number cites its source and AI drafts but never decides.
• ELLMENT, the offline LLM for E-2D crews answers a crew's question from the aircraft's own manuals and cites the page, with no network.
• TRACE, the offline S1000D and IETM viewer opens S1000D, MIL-STD-3001 and PDF technical manuals on a tablet with every marking intact.