What is a CMMC RPO?

EXECUTIVE BRIEF

As defense contractors plan out their compliance journeys, knowing what to look for in a third-party provider is key. Working with an RPO can help streamline your compliance journey and provide more predictable outcomes during your Level 2 assessment.

Here's what defense contractors need to know about RPOs:

• Accredited by Cyber AB, demonstrating the organization's knowledge of the CMMC framework and ability to guide contractors through their compliance journey
• RPOs adhere to a strict code of conduct, including provisions on professionalism, confidentiality, and lawful and ethical actions
• An RPO accreditation does not equate to a CMMC Level 2 certification - be sure to ask your third-party vendor about their RPO and CMMC status 

Dig deeper and continue learning below!

What Is a CMMC RPO?

A CMMC RPO (Registered Provider Organization) is a company accredited by the Cyber-AB (formerly called the CMMC Accreditation Body) to provide consulting and advisory services for organizations seeking Cybersecurity Maturity Model Certification (CMMC) compliance. RPOs help organizations prepare for CMMC assessment, but they do not conduct the official CMMC assessment itself; the actual assessment is done by a Certified Third-Party Assessor Organization (C3PAO).

What a CMMC RPO Does

An RPO’s primary role is to guide contractors through the CMMC certification process. They’re staffed with CMMC Registered Practitioners (RPs), trained to understand the intricacies of the NIST SP 800-171 framework and the unique challenges of the Defense Industrial Base.

Consulting: RPOs offer consulting and guidance to defense contractors by translating CMMC’s complex requirements into concrete, actionable steps for implementing policies and security controls.

Preparation: They assist with preparation by conducting pre-assessment reviews, supporting CMMC program planning, and helping with technical implementation tasks such as hardening networks and deploying cybersecurity tools.

Remediation: If a finding is identified during an official assessment, RPOs can offer direction on how to remediate gaps and bring the security environment back into alignment with CMMC expectations.

What a CMMC RPO Does Not Do

While Registered Provider Organizations play an important role in helping contractors prepare for CMMC, their authority has clear limits:

• RPOs can’t conduct official assessments: They aren’t authorized to perform the certified CMMC evaluation required for audit purposes.
• RPOs can’t issue a CMMC certification: Only an accredited C3PAO has the authority to carry out a final assessment and award certification status.
• RPOs can’t confer CMMC compliance by association: Their involvement and accreditation do not grant a contractor CMMC-certified status; the organization must still undergo a formal third-party assessment.

Why Work with an RPO?  

With thousands of contractors competing for DoD contracts, achieving compliance quickly and efficiently is critical. Here are the benefits of working with an RPO: 

1. They Simplify Complex Requirements  

Making your way through the CMMC ecosystem requires interpreting technical regulations like NIST SP 800-171 and DFARS clauses. RPOs bring expertise to help your team translate these complex cybersecurity requirements into actionable steps.

2. They Save Time and Resources  

Attempting to achieve and maintain compliance in-house often leads to wasted time and inefficiencies. Partnering with an RPO reduces the strain on internal resources, allowing your team to focus on core responsibilities while experts handle compliance preparation.

3. RPOs Help Ensure Your Readiness for Assessment  

RPOs can assist with gap assessments to identify areas that need improvement before a C3PAO review. This ensures your organization is fully prepared for the formal assessment, minimizing the risk of failing.

4. RPOS possess Expert Knowledge  

RPOs specialize in DoD cybersecurity compliance, offering targeted assistance and solutions tailored to your business. Whether you need help drafting a Plan of Action & Milestones (POA&M) or integrating secure, FedRAMP-compliant technologies, an RPO has the expertise to guide you.

5. RPOs Mitigate cyber Risks and Protect your Contracts  

Non-compliance isn’t just a technical failure—it’s a business risk. A failed assessment can disqualify you from critical DoD contracts. RPOs help mitigate this risk by proactively addressing vulnerabilities.

What’s the Difference Between a CMMC RPO and a C3PAO?

RPOs act as advisors. They help organizations seeking certification (OSCs) interpret CMMC requirements, develop policies, strengthen security practices, and implement the tools and documentation needed to meet their CMMC obligations. Their job is to ensure contractors enter the assessment phase fully prepared and confident in their compliance posture.

C3PAOs, on the other hand, function as official assessors. Only a C3PAO can perform the formal CMMC Level 2 assessment, review evidence, interview staff, test controls, and ultimately decide whether to recommend certification to the Cyber AB. They do not provide consulting or remediation support to the companies they assess—doing so would create a conflict of interest.

In simple terms: RPOs help you get ready; C3PAOs determine whether you’ve met the standard. Both are important in the CMMC marketplace, but only one has the authority to grant the certification required for DoD contracts.

CMMC RPO services 

Before beginning any advisory work, most DoD contractors sign an RPO agreement that outlines the scope of services, preparation activities, and responsibilities the RPO will provide during the CMMC readiness process. RPOs provide a range of specialized services designed to prepare DoD contractors for CMMC certification while addressing the unique requirements of the defense supply chain.

Below is a breakdown of the core services an RPO offers.

Tailored Solutions for the DoD Supply Chain  

One of the key advantages of working with an RPO is their understanding of the specialized challenges faced by contractors managing Controlled Unclassified Information (CUI) and Federal Contract Information (FCI). RPOs provide expert services beyond a generalist MSP's scope, including insider threat detection, secure supply chain processes, and customized risk management strategies.

Gap Analysis and Remediation Planning 

RPOs thoroughly assess your current cybersecurity practices against the applicable CMMC standards. This evaluation identifies gaps in compliance and provides a practical roadmap to remediate these deficiencies, ensuring your organization is fully prepared for the certification process.

System Security Plan and POA&M Development  

Developing a compliant System Security Plan (SSP) and POA&M is critical in achieving CMMC certification. RPOs create these tailored documents, ensuring they accurately reflect your cybersecurity strategy and align with certification requirements.

Preparation for NIST 800-171 Compliance  

CMMC Level 2 is built upon the 110 security controls of NIST SP 800-171, and RPOs can offer expert guidance in implementing these practices. This ensures that your organization achieves compliance and strengthens its overall security posture.

Technology Implementation Support  

Unlike generalist MSPs, RPOs specialize in recommending secure technologies that meet federal compliance standards. They provide technical implementation support by guiding organizations through tasks such as hardening networks, configuring role-based access controls, deploying endpoint protection, enabling logging and monitoring, and establishing secure CUI enclaves. They help ensure that each technical safeguard aligns with NIST 800-171 expectations and is properly documented so the organization is prepared for future assessment activities.

Pre-Assessment Preparation

Before a formal C3PAO review, RPOs help organizations verify that their controls are implemented and their documentation is complete. This often includes conducting a mock assessment, reviewing evidence for accuracy and completeness, validating that policies match actual practices, and confirming that the SSP and POA&M fully reflect the environment. Pre-assessment preparation reduces surprises during the official audit and gives teams the confidence that they can explain or demonstrate each control during interviews and testing.

Continuous Monitoring and Ongoing Compliance Support  

CMMC isn’t a one-time effort, and many organizations rely on RPOs for ongoing guidance as their environment evolves. This may include updating documentation after system changes, advising on new tools or configurations, helping interpret updated guidance from the DoD or Cyber AB, or reviewing evidence on a recurring basis. By staying engaged, RPOs help contractors maintain long-term compliance readiness and ensure they can quickly adjust their program as requirements, infrastructure, or business needs shift.

What Value Does a CMMC RPO Provide?  

While general MSPs may support IT operations, RPOs bring targeted expertise, certified experience, and a deep understanding of the defense sector’s unique demands. The result? Strategic support that aligns security with business success.

Organizations facing stringent regulations, like those in the defense sector, need a partner with specific knowledge and focus to address these challenges effectively. Here’s what sets RPOs apart.

1. Industry Focus

RPOs specialize in DoD cybersecurity regulations, ensuring a deep understanding of standards like NIST SP 800-171, DFARS, and CMMC 2.0. Generalist MSPs often lack this level of expertise.

2. Certified Expertise

RPOs are accredited by Cyber-AB and employ RPs, assuring that their guidance meets the highest standards of professionalism and compliance.

3. Cost Efficiency  

While RPOs may appear more expensive upfront, their precise understanding of compliance challenges leads to cost savings by avoiding errors and unnecessary delays.

4. Custom-Tailored Solutions  

RPOs offer solutions explicitly designed for defense contractors, ensuring seamless integration within your organization’s infrastructure.

How to Choose the Right CMMC RPO for Your Business

Not all RPOs are created equal. Selecting the right partner is crucial for a smooth compliance process. Consider the following factors. 

1. Look for DoD experience. Look for an RPO with a proven track record of working within the DIB and preparing clients for CMMC requirements.     

2. Check Cyber-AB RPO credentials. Ensure the provider is an officially recognized CMMC Registered Provider Organization through Cyber-AB. 

3. Ensure deep familiarity with NIST SP 800-171 and CMMC 2.0. They should demonstrate a thorough understanding of both frameworks and their application to DoD contracts.

4. Verify they’re a qualified expert. Confirm that they have RPs on staff with hands-on experience guiding OSCs. 

5. Ask if they’re CMMC certified. Look for opportunities to further streamline your compliance journey and increase the likelihood of a successful outcome by working with a CMMC certified RPO. 

ISI became one of the first MSPs in the nation to earn a CMMC Level 2 Certificate of Status on March 10, 2025, demonstrating that our own security program meets the same rigorous NIST 800-171 controls we help clients implement.

Key Questions to Ask 

Before settling on an RPO, ask potential candidates the following questions:

• Are you a Cyber-AB Registered Provider Organization? If not, do you have any Registered Practitioners on staff?
• How many DIB organizations have you supported?  
• Can you provide testimonials or case studies showcasing successful compliance journeys?  
• Do you offer ongoing compliance monitoring after certification?  
• What is your average turnaround time for preparation and certification readiness?

Simplify CMMC Compliance with Expert RPO Guidance 

CMMC takes a unified effort that connects your people, your systems, and your security practices. With ISI, you get a single, purpose-built RPO team that supports every part of that journey, from facilities clearance and program management to cybersecurity engineering and managed IT. No handoffs. No fractured vendors. No gaps for auditors to find.

If you’re ready to simplify compliance, strengthen your security posture, and stay contract-ready with confidence, we’re here to help.

FAQ

What Is the Difference between a CMMC RPO and a C3PAO?

RPOs guide and prepare organizations for CMMC assessments, offering consulting services related to compliance readiness. C3PAOs are authorized to conduct official third-party assessments for CMMC certification.

What Is RPO Certification?

RPO certification is the official recognition granted by the Cyber AB to organizations that meet the standards required to serve as Registered Provider Organizations. To qualify, an RPO must adhere to a strict code of professional conduct, employ background-checked Registered Practitioners, and demonstrate knowledge of the CMMC model and its maturity levels. While RPO certification does not authorize an organization to perform assessments, it confirms that the provider is approved to deliver CMMC readiness consulting.

What Is a CMMC RP?

A CMMC Registered Practitioner (RP) is an individual trained and listed by the Cyber AB to provide advisory services and help contractors understand and implement required security practices. RPs must pass a background check, follow the official code of professional conduct, and maintain familiarity with CMMC requirements, NIST 800-171, related frameworks such as ISO standards, and common tech environments like Microsoft 365 GCC High. They often serve as the primary consultants delivering hands-on guidance under an RPO.

Why Do I Need a CMMC RPO?

A CMMC RPO helps contractors interpret complex requirements, prepare documentation, and align their security program with the appropriate maturity levels before an assessment. RPOs provide credible, reliable expertise that reduces the risk of misinterpretation or costly remediation later. For many small and midsize organizations, an RPO ensures readiness long before a C3PAO arrives.

What Services Does a CMMC RPO Offer?

A CMMC RPO provides readiness-focused services such as gap analyses, policy development, SSP and POA&M support, secure architecture guidance (including Microsoft or hybrid environments), and preparation for formal assessments. RPOs do not conduct assessments themselves, but they translate CMMC’s security requirements and maturity levels into practical steps your organization can implement. Their services are governed by the CMMC-AB and delivered by background-checked Registered Practitioners.

What Value Does a CMMC RPO Provide?

A CMMC RPO adds value by helping contractors avoid costly mistakes, accelerate readiness, and confidently meet the security practices required for certification. Because RPOs follow a formal code of professional conduct, use trained and background-checked RPs, and often bring experience across frameworks like NIST and ISO, they provide structured, credible support tailored to your environment. For organizations navigating tools such as Microsoft 365 or standing up compliant enclaves, an RPO ensures your investment leads to true audit-ready compliance.