FAR Part 15: Contracting by Negotiation
FAR Part 15 governs the most formal and rigorous procurement process in federal acquisition: contracting by negotiation. It is used for complex acquisitions where the government evaluates proposals against multiple factors — not just the lowest price — to select the best value solution.
This guide covers the source selection process, evaluation factors, how discussions work, Best and Final Offers, and strategies for competing effectively under Part 15.
100M+ government records · 300+ gov/news sources · Updated hourly
Source Selection Process Overview
Source selection under FAR Part 15 is a structured process that the government uses to evaluate competing proposals and select the one that offers the best value. The process begins with a Source Selection Plan (SSP) that defines how proposals will be evaluated, and ends with a Source Selection Decision Document (SSDD) that justifies the award decision.
The key participants in source selection include:
- Source Selection Authority (SSA): The official responsible for making the final award decision. For high-value or complex acquisitions, this may be a senior official.
- Source Selection Evaluation Board (SSEB): The team of evaluators who review proposals against the stated evaluation criteria and assign ratings.
- Source Selection Advisory Council (SSAC): For major acquisitions, a senior-level body that reviews SSEB findings and provides recommendations to the SSA.
- Contracting Officer (CO): Manages the procurement process, conducts discussions, and executes the contract.
The two primary source selection approaches are Lowest Price Technically Acceptable (LPTA), where the lowest-priced proposal meeting all requirements wins, and Best Value Tradeoff, where the government weighs technical merit against price and may pay more for a technically superior solution.
Competitive Proposals vs Sole Source
FAR Part 15 primarily covers competitive proposals, but it also addresses sole source (noncompetitive) negotiations. Understanding both tracks is important for contractors.
Competitive Proposals
The standard approach under FAR 15.3. Multiple offerors submit proposals in response to a solicitation that defines the government's requirements and evaluation criteria.
- Open to all responsible offerors (or limited by set-aside)
- Evaluation factors stated in the solicitation
- Government may establish a competitive range
- Discussions optional but, if held, must be meaningful
- Award based on best value to the government
Sole Source Negotiation
When competition is not feasible, the government negotiates directly with a single source. Requires a Justification and Approval (J&A) document citing one of seven statutory authorities under FAR 6.302.
- Single offeror submits a proposal
- Certified cost or pricing data usually required (TINA)
- Government conducts price or cost analysis
- Negotiations focus on fair and reasonable pricing
- J&A must be approved at appropriate level
Evaluation Factors and Subfactors
FAR 15.304 requires that evaluation factors and significant subfactors be stated in the solicitation along with their relative importance. The government must evaluate proposals solely on the factors and subfactors identified — it cannot introduce new criteria during evaluation.
Common evaluation factors include:
Technical Approach / Management Approach
How you will perform the work. Evaluators assess your understanding of requirements, proposed methodology, staffing plan, quality control, risk mitigation, and innovation. This is typically the most heavily weighted non-price factor.
Usually weighted highest for complex services
Past Performance
Your track record on similar contracts. Evaluators review CPARS ratings, reference questionnaires, and relevance of prior work. A history of on-time, on-budget delivery with high customer satisfaction scores well. FAR requires past performance to be evaluated for all negotiated competitive acquisitions over $1 million.
Required for acquisitions over $1M
Price / Cost
Your proposed pricing. For best value tradeoffs, price is evaluated but may be less important than technical factors. For LPTA, price is the determining factor once technical acceptability is established. Price must always be evaluated and is typically the second-most important factor after technical merit.
Always evaluated; weight varies by approach
Small Business Participation
Your plan for subcontracting to small businesses. For contracts over $750K ($1.5M for construction), you must submit a small business subcontracting plan. Some solicitations evaluate small business participation as a separate factor.
Sometimes a standalone factor
Key Personnel
Qualifications and experience of proposed key staff. Evaluators assess whether your named personnel have the skills, certifications, and experience required for the effort. Resumes must demonstrate relevant, verifiable experience.
Often a subfactor under Technical
A critical rule: evaluation factors must be stated in order of relative importance. If technical is more important than price, the solicitation must say so. Phrases like “technical and past performance, when combined, are significantly more important than price” signal a best value tradeoff. This tells you where to invest your proposal effort.
Discussions, Clarifications, and Communications
FAR Part 15 carefully distinguishes between different types of exchanges between the government and offerors during source selection. Understanding these distinctions is critical because they determine what you can and cannot change in your proposal.
Communications (FAR 15.306(b)): Limited exchanges before the competitive range is established. The government may address ambiguities, allow offerors to address past performance issues, or resolve minor informational problems. These do not open the door to proposal revisions.
Clarifications (FAR 15.306(a)): Limited exchanges used when award will be made without discussions. Clarifications may address clerical errors, minor ambiguities, or questions about the proposal. They do not allow offerors to materially change their proposals.
Discussions (FAR 15.306(d)): Meaningful negotiations with offerors in the competitive range. The government must identify deficiencies, significant weaknesses, and adverse past performance to each offeror. Discussions are tailored to each proposal — the government discusses only the issues relevant to that offeror's proposal. After discussions, offerors submit Final Proposal Revisions.
The line between clarifications and discussions is a frequent basis for GAO bid protests. If the government asks you a question that goes beyond resolving an ambiguity and effectively allows you to improve your proposal, that exchange may constitute discussions — and if the government did not intend to have discussions, it creates a protestable issue.
Best and Final Offers (BAFOs) / Final Proposal Revisions
After discussions are concluded, the contracting officer requests Final Proposal Revisions (FPRs) from all offerors remaining in the competitive range. While commonly called “Best and Final Offers” or BAFOs, the FAR technically refers to these as “Final Proposal Revisions” (FAR 15.307).
Key points about FPRs:
- You can revise any aspect of your proposal, not just the issues raised in discussions
- The government sets a common deadline for all offerors to submit FPRs
- If you do not submit a revision, your original proposal (as amended by any revisions during discussions) is evaluated
- The government evaluates FPRs and makes its award decision — no further discussions occur
- There is generally only one round of FPRs, though the government can reopen discussions in limited circumstances
Strategy tip: Use the FPR as an opportunity to address every weakness identified during discussions, sharpen your technical approach based on what you learned, and present your most competitive price. This is your last opportunity to influence the evaluation.
Advisory Multi-Step Process
FAR 15.202 authorizes an advisory multi-step process that allows the government to screen potential offerors before they invest in preparing full proposals. This two-phase approach benefits both sides:
Phase One: The government issues a presolicitation notice or RFI requesting information about offerors' qualifications, experience, and technical capabilities. Based on these responses, the government provides advisory feedback on whether the offeror is likely to be a viable competitor.
Phase Two: The government issues the full solicitation. All offerors can submit proposals regardless of Phase One feedback, but the advisory input helps companies make informed bid/no-bid decisions.
This process is particularly valuable for large, complex acquisitions where proposal costs are significant. If the government advises that your qualifications are unlikely to be competitive, you can save the substantial investment of preparing a full proposal and redirect those resources to more winnable opportunities.
Note that the advisory multi-step process is distinct from the two-phase design-build selection procedures under FAR 36.3, which is used specifically for construction and architect-engineer services.
Frequently Asked Questions
What is the difference between FAR Part 15 and FAR Part 8 or Part 12?
FAR Part 15 covers contracting by negotiation, used for complex acquisitions where the government needs to evaluate proposals against multiple factors (not just price). FAR Part 8 governs required sources of supplies (GSA Schedules, AbilityOne). FAR Part 12 covers simplified commercial item acquisitions. Part 15 is used when the acquisition is too complex for simplified procedures and requires a formal source selection process.
What is a competitive range and how is it determined?
The competitive range is the subset of proposals that have a reasonable chance of being selected for award. After initial evaluation, the contracting officer establishes the competitive range based on ratings and price. Proposals clearly not competitive are excluded. Offerors in the competitive range may then participate in discussions with the government to address weaknesses and deficiencies in their proposals.
Are discussions mandatory in a FAR Part 15 acquisition?
No. The contracting officer may award without discussions if the solicitation states that the government intends to award without discussions and the proposals are evaluated as submitted. However, if discussions are conducted, they must be meaningful — the government must point out weaknesses, deficiencies, and adverse past performance information, and give offerors an opportunity to respond.
What is the difference between clarifications and discussions?
Clarifications are limited exchanges to resolve minor uncertainties or clerical errors. They do not give offerors an opportunity to revise their proposals. Discussions (also called negotiations) are more substantive exchanges where the government identifies deficiencies, weaknesses, and significant weaknesses, and offerors have the opportunity to revise their proposals. Discussions trigger the requirement for a Final Proposal Revision (formerly BAFO).
Track FAR Part 15 Negotiated Solicitations
Search across SAM.gov for solicitations using FAR Part 15 competitive negotiation procedures. Filter by evaluation approach, agency, and contract value to find best value opportunities.