Source Selection Preparation and Evaluation

Definition: Source selection is a critical phase of the pre-award procurement process. It is often thought of as making tradeoffs among offerors' proposals to determine the best value offer. According to Federal Acquisition Regulation (FAR) 15.3, source selection is the "selection of a source or sources in competitive negotiated acquisitions ... The objective of source selection is to select the proposal that represents the best value" [1].

Keywords: advisory multi-step process, best value determination, down-select, evaluation, proposal evaluation, source selection, technical evaluation

MITRE SE Roles and Expectations: MITRE systems engineers (SEs) are expected to create technical and engineering portions of request for proposal (RFP) documentation (requirements documents, statements of work, evaluation criteria), assist in developing the technical portions of source selection plans, and assist in the technical evaluation of bidders. MITRE SEs also are expected to encourage agency program and acquisition managers to build effective processes into their acquisition strategies. Increasing the program office's likelihood of success often requires acting as an intermediary between the government and contractors to objectively and independently assess the degree to which proposed solutions or courses of action will provide the capabilities needed to meet the government's needs. This includes conducting assessments of the risk inherent in proposed solutions—including strategies for acquiring (or implementing) them—and identifying actionable options for mitigating those risks.


Source selection is not an isolated aspect of the acquisition life cycle; instead, it is a key phase of the life cycle shown in Figure 1. For source selection to be successful, the precursor phases of the life cycle (need identification, market research, requirements definition, strong acquisition planning, solicitation development, and proposal solicitation) must be completed effectively.

The source selection approach should be captured in a source selection plan. The plan should include the proposal evaluation criteria. Selecting appropriate evaluation factors is one of the most important steps in the entire source selection process. The source selection plan explains how proposals are to be solicited and evaluated to make selection decisions. It defines the roles of the source selection team members. A realistic schedule also should be included in the plan.

Figure 1. Key Phases of the Acquisition Life Cycle

Best Practices and Lessons Learned

Advocate the right definition of success. Some organizations define "acquisition success" as the awarding of the contract. Once the contract is awarded (without a protest), victory is declared. Although contract award is one of several important milestones, this limited view of acquisition tends to overlook the need to adequately consider what it will take to successfully execute the acquisition effort in a way that achieves the desired outcomes. It leads to a "ready, fire, aim" approach to acquisition planning. Advocate for a broader view of acquisition success, one that balances the desire to award a contract quickly with adequate planning, program management, and systems engineering across the entire system or capability life cycle.

The importance of planning. The importance of conducting adequate acquisition planning before releasing the RFP cannot be overstated. This includes encouraging clients to take the time to conduct market research and to dialog with industry so the government becomes a smart buyer that recognizes what is available in the marketplace, including the risks and opportunities associated with being able to acquire solutions that meet their needs. This insight allows the government to develop a more effective source selection strategy, which includes choosing more meaningful evaluation factors (or criteria) that focus on key discriminators, linked to outcome metrics. Concentrating on a few key differentiating factors can also translate into a need for less proposal information instead of asking for "everything." Asking for everything tends to occur when the government is not certain about what is most important among its requirements. Adequate acquisition planning helps ensure that the source selection process will go smoothly, increases the probability of selecting the best solution, and reduces the risk of protest.

Maintain the right focus. Focusing on mission/business outcomes instead of detailed technical specifications broadens the trade space of potential innovative solutions that industry (potential contractors) may offer. It can increase industry's ability to use commercial items and/or non-developmental items to fulfill government needs.

Follow your process. The evaluation documentation must provide a strong rationale for the selection decision. During the proposal evaluation phase, a critical lesson is to ensure that the evaluation team does not deviate from the stated RFP evaluation factors. Government Accountability Office decisions clearly indicate that the use of factors other than those published in the RFP almost guarantees that a bid protest will be sustained. At a minimum, the source selection documentation must identify weaknesses, significant weaknesses, and deficiencies as defined by FAR 15.001 Definitions [1]. Good documentation also identifies strengths and risks.

The importance of industry exchanges. Increased communication with industry through pre-solicitation notices, information exchanges, and draft RFPs makes the acquisition process more transparent and may lower the likelihood of a protest. These techniques can be an effective way to increase competition, especially when there is a strong incumbent. Exchanges with industry are especially important when the procurement requirements are complex.

Handling sensitive proposal information—a critical requirement. To maintain the integrity of procurement, sensitive source selection information must be handled with discretion to avoid compromise. All government team participants share the critical responsibility to ensure that source selection and proprietary information is not disclosed. There is no room for error. Any lapses by MITRE individuals not only could compromise the integrity of a federal procurement but also could damage MITRE's relationship with the government.

Clarity of evaluation factors. It is not unusual for the government to ask MITRE SEs to help draft proposal evaluation factors (Section M) for a solicitation. The focus should be on the key discriminators that will help distinguish one proposal from another. Cost must always be one of the factors, along with such factors as mission capability, similar experience, past performance, and key personnel. Many solicitations are often vague about the relative weights among such evaluation factors as cost. These ambiguities often lead to successful protests. It is important to do everything possible to ensure that the relative weights of the factors are as clear as possible in the minds of the potential offerors and the government evaluation team.

Articles Under This Topic

The article Picking the Right Contractor describes best practices and lessons learned in the pre-proposal and selection process, including ways to involve industry to improve the likelihood of a better source selection outcome.

The article RFP Preparation and Source Selection walks you through the RFP process, typical MITRE systems engineering roles, and the important points of the selection process.

Both articles contain best practices and lessons learned for the preparation and evaluation processes.

References and Resources

  1. Federal Acquisition Regulation (FAR):
    • FAR 15.001 Definitions
    • FAR 15.1 Source Selection Processes and Techniques
    • FAR 15.202 Advisory Multi-step Process
    • FAR 15.3 Source Selection

Additional References and Resources

National Contract Management Association (NCMA) World Congress, April 22–25, 2007, Source Selection: Best Practices in Streamlining the Process.


Download the SEG

MITRE's Systems Engineering Guide

Download for EPUB
Download for Amazon Kindle
Download a PDF

Contact the SEG Team