Proposal Strategy

Source Selection & Evaluation Guide: How Government Evaluates Your Proposal

Understand how government agencies evaluate proposals. Learn about source selection processes, evaluation factors, rating methods, selection procedures, and how to position your proposal for success.

Sarah Chen
December 28, 2025
14 min read

Quick Answer

Source selection is the process by which the government evaluates proposals and selects a contractor. Evaluators rate proposals against factors stated in the solicitation, with price always evaluated. Understanding how evaluations work—from factor weighting to rating scales—helps you write proposals that score higher and win more contracts.

FAR 15
Source Selection
SSA
Selection Authority
SSEB
Evaluation Board
SSAC
Advisory Council

Source Selection Basics

Source selection is the government's formal process for evaluating competing proposals and selecting the contractor that represents the best value. FAR Part 15 governs competitive negotiated procurements and establishes source selection requirements.

The key principle: agencies must select based on factors stated in the solicitation. Evaluators cannot use unstated criteria or change factor weightings after proposals are received. Understanding this gives you a roadmap for proposal success.

Source Selection Requirements

  • Stated Factors: All evaluation factors and significant subfactors must be in the solicitation
  • Relative Importance: Solicitation must disclose factor weightings or order of importance
  • Price Always Evaluated: Cost or price must be evaluated in every source selection
  • Quality Evaluation: Quality of product or service must be addressed
  • Past Performance: Must be evaluated in all negotiated acquisitions over $250K

Evaluation Factors

Evaluation factors are the criteria used to assess proposals. Understanding common factors and their relative importance helps you allocate proposal resources effectively.

Common Technical Factors

  • Technical Approach: How you'll accomplish the work
  • Management Approach: How you'll manage the project
  • Key Personnel: Qualifications of key staff
  • Corporate Experience: Relevant company history
  • Staffing Plan: Proposed workforce and structure
  • Risk Mitigation: How you'll handle risks

Other Common Factors

  • Past Performance: Historical contract performance
  • Price/Cost: Proposed pricing and realism
  • Small Business Participation: Subcontracting plans
  • Transition Plan: For successor contracts
  • Security: Clearances and compliance
  • Oral Presentations: In-person capability demo

Example Factor Weightings

Technical ApproachMost Important
Past PerformanceEqual to Technical
ManagementLess Important
PriceSignificantly Less Important than Non-Price Combined

Rating Methods

Agencies use various rating methods to evaluate proposals. Understanding how ratings work helps you target the highest possible scores.

Common Adjectival Rating Scales

Outstanding/Exceptional

Significantly exceeds requirements. Strengths far outweigh weaknesses. Low risk of unsuccessful performance.

Good/Very Good

Exceeds some requirements. Strengths outweigh weaknesses. Minor risk of unsuccessful performance.

Acceptable/Satisfactory

Meets requirements. Strengths and weaknesses balanced. Moderate risk but correctable.

Marginal

Fails to meet some requirements. Weaknesses outweigh strengths. High risk without correction.

Unacceptable

Fails to meet requirements. Deficiencies cannot be corrected. Unacceptable risk.

Strengths & Weaknesses

  • Strength: Aspect that exceeds requirements
  • Weakness: Aspect that doesn't fully meet requirements
  • Deficiency: Failure to meet a requirement
  • Risk: Potential for unsuccessful performance

Color Ratings (DoD)

  • Blue: Outstanding
  • Green: Acceptable/Good
  • Yellow: Marginal
  • Red: Unacceptable

The Evaluation Team

Understanding who evaluates your proposal helps you write for your audience.

Source Selection Roles

Source Selection Authority (SSA)

Makes final selection decision. Often senior executive or contracting officer. Reviews evaluation results and makes trade-off decisions.

Source Selection Evaluation Board (SSEB)

Evaluates proposals against criteria. Technical, cost, and past performance evaluators. Documents strengths, weaknesses, and ratings.

Source Selection Advisory Council (SSAC)

Advises SSA on evaluation results. Reviews SSEB findings and provides recommendations. Used on larger acquisitions.

Contracting Officer

Manages procurement process. Ensures compliance with regulations. May serve as SSA on smaller procurements.

Know Your Evaluators

Technical evaluators are often subject matter experts, not professional proposal reviewers. Write clearly, use plain language, and make compliance obvious. Don't assume evaluators will search for information.

Evaluation Process

1

Proposal Receipt & Distribution

Proposals received by deadline, logged, and distributed to evaluation team members.

2

Individual Evaluation

Each evaluator independently reviews assigned factors, documents strengths/weaknesses, assigns initial ratings.

3

Consensus Evaluation

Evaluation team meets to discuss findings, resolve differences, reach consensus ratings.

4

Competitive Range (if applicable)

SSA determines which offerors are in competitive range for discussions. Others may be eliminated.

5

Discussions (if held)

Government discusses weaknesses/deficiencies with offerors, who submit revised proposals.

6

Best Value Determination & Award

SSA makes trade-off analysis (best value) or selects lowest acceptable price (LPTA). Award made.

Positioning for Success

Address Every Factor

Organize your proposal to match evaluation factors. Make it easy for evaluators to find responsive content.

Aim for Strengths

Don't just meet requirements—exceed them to earn strengths. Strengths differentiate you from competitors.

Eliminate Weaknesses

Review proposal for gaps. Address every requirement explicitly. Weaknesses lower ratings even if you have strengths.

Show, Don't Tell

Provide evidence and specifics, not unsupported claims. Evaluators are skeptical of assertions without proof.

Use Clear Language

Write for busy evaluators. Use headers, bullets, and compliance matrices. Don't make them search for answers.

Allocate by Weight

Spend proposal effort proportional to factor importance. Don't over-invest in low-weight factors.

Post-Award Debriefs

Win or lose, debriefs provide valuable insight into how your proposal was evaluated.

What Debriefs Include

Your Proposal

  • • Your strengths and weaknesses
  • • Your ratings by factor
  • • Rationale for ratings
  • • Areas for improvement

Overall Competition

  • • Awardee's strengths (general)
  • • Relative ranking (if applicable)
  • • Trade-off rationale
  • • Small business goals (if relevant)

Maximizing Debrief Value

  • Request Promptly: Request debrief within 3 days of notification
  • Prepare Questions: Have specific questions ready about your evaluation
  • Take Notes: Document everything for future proposals
  • Assess Protest Grounds: Evaluate if evaluation was proper
  • Apply Lessons: Use feedback to improve future proposals

Frequently Asked Questions

Can the government change evaluation factors after receiving proposals?

No. Evaluators must use only the factors and weightings stated in the solicitation. Using unstated factors or changing weights is protestable.

How do I know if I'm in the competitive range?

If you're excluded from the competitive range, the agency must notify you promptly. If you receive discussion questions, you're in the competitive range. No news during evaluation usually means you're still being considered.

What if I disagree with my evaluation?

First, request a debrief to understand the evaluation. If you believe the evaluation was improper (unstated factors, unequal treatment, etc.), you may have grounds for protest. Consult with counsel before proceeding.

Does lowest price always win in best value?

No. In best value trade-off, the SSA can select a higher-priced proposal if superior technical merit justifies the premium. The solicitation's factor weighting guides this trade-off.

How long do evaluations take?

It varies widely—from weeks to months depending on complexity, number of proposals, and agency workload. Large acquisitions with oral presentations and multiple evaluation rounds take longest.

Find Contract Opportunities

Understanding source selection is just the start. BidFinds helps you find opportunities where your strengths match evaluation criteria for higher win rates.

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