CMMC CAP Explained: Your Complete Guide To Assessment Preparation

If you’re bidding on Department of Defense (DoD) contracts, you’ll need Cybersecurity Maturity Model Certification (CMMC).

To ensure CMMC assessments are conducted consistently and with integrity, the CMMC assessment process (CAP) official guide is used during the final audit. In this guide, we cover what the CAP requires, how it’s used during the assessment, and the best ways to prepare your organization to reduce surprises and mistakes on audit day.

Whether you’re a prime contractor with the DoD or a subcontractor in the supply chain, this guide addresses key requirements in the CMMC CAP so your organization can achieve full CMMC compliance and get certified.

What is the CMMC CAP?

The CMMC Assessment Process (CAP) is the official CMMC assessment guide used in the final CMMC 2.0 assessment to determine whether an organization meets strict CMMC requirements. It ensures your final assessment is fair, consistent, and recognized across the entire defense supply chain.

The DoD has to constantly safeguard the Defense Industrial Base (DIB) from cyber attacks and data breaches, especially for vendors that handle Controlled Unclassified Information (CUI). While vendors at CMMC level 1 that handle Federal Contract Information (FCI) only need to self-attest, CMMC certification is required for vendors at CMMC level 2 and 3.  

CMMC CAP was created by Cyber AB, which is the partner of the DoD responsible for overseeing the CMMC program. This guide sets the rules every Certified CMMC third-party assessment organization (C3PAO) must follow in the final audit to keep their evaluations objective and consistent.

• Purpose: The CAP outlines the process to standardize how CMMC assessments are performed, which ensures every vendor is measured against the same security controls and evidence requirements.
• Scope: CMMC CAP applies specifically to Level 2 assessments in the CMMC model, which cover contractors and subcontractors that handle Controlled Unclassified Information (CUI).
• Authority: Because it’s part of the official CMMC framework, any organization seeking a Level 2 certification must undergo an assessment conducted strictly against the CAP by a C3PAO.

Who Uses The CMMC CAP?

Any organization involved in a CMMC Level 2 assessment is expected to follow the CMMC Assessment Process (CAP). This includes:

• Certified Third-Party Assessment Organizations (C3PAOs): These are independent organizations accredited by the Cyber AB to conduct official CMMC assessments for DoD contractors. They must use the CAP every time they assess a vendor.
• Organizations Seeking Certification (OSCs): Defense contractors, subcontractors, and suppliers that want to work with the DoD. If you handle Controlled Unclassified Information (CUI), you are required to prepare and present documentation according to the CAP.
• Defense Industrial Base (DIB) Companies: Any organization in the DoD supply chain that handles CUI requires CMMC Level 2 certification, due to the 2025 DFARS clause 252.204-7021. You will need to prove that you maintain compliance and readiness according to the CAP.
• Assessment Team Members: Team members in a C3PAO organization, including CMMC certified Assessors (CCAs) and Certified CMMC Professionals (CCPs) apply the CAP’s methodology while performing and documenting assessments.

The Four Phases of the CAP

The CMMC CAP breaks down into four straightforward phases that keep every Level 2 assessment thorough and consistent.

1. Plan and Prepare

Get your evidence ready now so you're prepared when the full CMMC Level 2 assessment starts. In this phase, you'll need all your documents and proof points organized before any testing kicks off.

Your C3PAO will check that you're ready by reviewing key documents like your System Security Plan (SSP), asset inventories, and cloud provider details. They'll also confirm your assessment scope and overall readiness, then complete the pre-assessment form.

2. Conduct the Assessment

During the CMMC level 2 assessment, your implementation of security requirements will be evaluated against the CAP to check is assessment objectives are met.

This phase is carried out by a C3PAO firm, which will utilize an assessment team to review current security controls, collect necessary evidence and documentation including policies, logs, and configuration files, to conduct assessment scoring. During this phase, the lead assessor will likely meet with your organization in-person to check progress and address challenges in real-time.

3. Report Assessment Results

Your results will be finalized and documented by the C3PAO assessment team, with a formal quality assurance review conducted by a CCA outside the assessment team.

To ensure accuracy and consistency, findings are documented into a standardized report before being presented to your organization. The final assessment is submitted into the DoD CMMC system and the DoD will review the report again for completeness. You are expected to retain all assessment records for three years, due to the validity of the certification.  

4. Issue Certification and Close Out Findings

Finally, you’ll need to address and close out your Plan of Action and Milestones (POA&M) and remediation tasks. The C3PAO then validates this work, and once you meet all requirements, you receive your CMMC Level 2 certification.

How To Scope Your CMMC Assessment

1. Identify Controlled Unclassified Information (CUI)

Start by identifying all the CUI your organization handles within the scope of your DoD contract. This may include blueprints, reports, and technical drawings. Check how CUI flows across your network to illustrate the path and identify each system, app, and user that handles it.

2. Document System Boundaries

Create an inventory once CUI locations are known. Document how CUI is handled, processed, and stored, with network and data flow diagrams. Check that this meets the requirements of NIST SP 800-171. To ensure nothing is missed during this step, remember to include connections to cloud or third-party providers.

3. Avoid Common Scoping Mistakes

Don’t underestimate your full environment. Define specific boundaries for your CMMC environment, account for remote work access points, and double check you are maintaining a complete asset inventory, including ones that interact with CUI in less obvious ways — like work mobile phones.

4. Review Responsibilities With Stakeholders

To ensure everyone is kept accountable, identify key stakeholders and assign roles across IT, leadership teams, legal departments, subcontractors, and key vendors. Detail responsibilities for communication, body of evidence gathering, and updates.

Getting CMMC Certified: Next Steps

Once you've completed CMMC scoping and identified gaps, you need to focus on your final assessment. Here's what to do next:

• Build a timeline: Map out each assessment prep step realistically, including milestones for gap remediation, control implementation, and evidence collection. Factor in time for internal reviews and rework so you don't get rushed.
• Allocate resources early: Secure the right budget, tools, and key personnel as soon as possible, to keep the flow efficient.
• Prepare and train your team: Ensure key staff understand CMMC CAP requirements, how it will be assessed, and their role in interviews or evidence gathering.
• Organize documentation: Put all key documents (policies, procedures, logs, and system diagrams) in one centralized, easy-to-access repository. This cuts down on repeat requests.

Go deeper: Check out our full CMMC compliance checklist here.

Want to streamline your CMMC assessment process? Workstreet is an AI-powered CMMC RPO. We help companies build comprehensive defense-grade security programs that meet Level 2 requirements and protect Controlled Unclassified Information (CUI).

Schedule a call to get CMMC compliant fast.

CMMC CAP FAQs

What happens if my organization fails a CMMC Level 2 assessment?

You will receive a detailed findings report and should create a Plan of Action & Milestones (POA&M) to close any gaps. After remediation, the C3PAO will reassess before you can get certified.

How long does a typical CMMC Level 2 assessment take?

Most assessments can last several weeks to a month, from preparation to receiving the final certification. However, this will depend on your organization’s size, scope, and complexity.

Do cloud service providers need FedRAMP Moderate certification?

Yes, any cloud provider handling CUI must hold FedRAMP Moderate baseline authorization or show equivalent security controls. This will be documented and verified during the assessment.

How often is recertification required?

CMMC level 2 certification will remain valid for three years. It’s mandatory to provide an annual affirmation of compliance.

What’s the difference between a self-assessment and the official CAP assessment?

A self-assessment is used for CMMC level 1 certification. CAP will be used for the CMMC level 2 certification assessment, which has to be performed by an accredited C3PAO.