Plan of Action and Milestones is the requirement behind the document that tracks how your unmet security requirements will be fixed. It is part of the Security Assessment and Monitoring (03.12) family, and it is where findings from assessments and monitoring become tracked remediation commitments. Plan of Action and Milestones (03.12.02) has two (2) parts: develop a plan of action and milestones (POAM) that documents planned remediation actions and reduces or eliminates known vulnerabilities, and update the existing POAM based on findings from assessments, audits or reviews, and continuous monitoring. Per the NIST discussion, POAMs describe how unsatisfied security requirements will be met, they can be combined with or separate from the system security plan, and federal agencies may use the system security plan and POAM as inputs to decisions about whether to process Controlled Unclassified Information (CUI) on a nonfederal system.
A common difficulty with this requirement is treating the POAM as a static list built once for an assessment. R3 makes the update obligation explicit and ties it to three sources: assessments, audits or reviews, and continuous monitoring. A POAM that is created for a certification and never updated as new findings arrive does not satisfy the requirement, since remediation planning is meant to be a living process.
Where things stand for companies facing the transition from NIST 800-171 R2 to R3:
The following is reproduced verbatim from NIST 800-171 R3, requirement 03.12.02 Plan of Action and Milestones. Only the formatting has been adjusted for readability. This requirement has two (2) lettered parts, each with numbered sub-parts:
The source control is CA-05 from NIST 800-53. There are no Organization-Defined Parameters (ODPs). Per the NIST discussion, organizations use POAMs to describe how unsatisfied security requirements will be met and how planned mitigations will be implemented, and system security plans and POAMs can be separate or combined documents in any format. You can read the requirement directly at NIST 800-171 R3, 03.12.02 (p. 56).
None (0). Requirement 03.12.02 contains no bracketed assignment, so there is no organization-defined value to select and nothing for the DoD to specify. The requirement applies as written.
Your System Security Plan (SSP) narrative for 03.12.02 therefore records how the requirement is implemented rather than a parameter you chose.
NIST 800-171A R3 breaks 03.12.02 into five (5) determination statements, and it has no Organization-Defined Parameters (ODPs). These AOs are:
Part a covers developing the POAM and part b covers updating it from three sources. The full guidance on assessment methods and objects, is in NIST 800-171A R3, 03.12.02 (p. 72).
Examine: security assessment and monitoring policy and procedures; procedures for plans of action and milestones; security assessment plan; security assessment report; security assessment evidence; plan of action and milestones; system security plan.
Interview: personnel with plans of action and milestones development and implementation responsibilities; personnel with information security responsibilities.
Test: mechanisms for developing, implementing, and maintaining plans of action and milestones.
03.12.02 maps from NIST 800-171 R2 requirement 3.12.2 (develop and implement plans of action designed to correct deficiencies and reduce or eliminate vulnerabilities in organizational systems):
Mapped against the five (5) AOs, two (2) are indirect (moderate effort), two (2) are net new, and one (1) has no clear mapping, with the last two (2) categories both counting as significant effort. Developing the POAM carries forward, but the explicit obligation to update it based on audits or reviews and continuous monitoring is new, and updating from assessment findings does not trace cleanly to a R2 objective. Three of the five (5) objectives are significant effort, all concentrated on keeping the POAM current.
Source Control in NIST 800-53 R5:
Secure Controls Framework (SCF) Crosswalk
Organizations running a single control set across multiple frameworks can satisfy 03.12.02 through the following SCF controls:
The crosswalks from NIST 800-171 R3 and NIST 800-171A R3 to the SCF are available at no cost through the SCF Set Theory Relationship Mapping (STRM): https://securecontrolsframework.com/start-here/set-theory-relationship-mapping-strm. The STRM also carries the relationship type for each mapping (Equal, Subset Of, Intersects With), which tells you whether an SCF control fully satisfies the requirement or only part of it. Mapping above taken from SCF 2026.3.
The following are issues teams may encounter rather than certainties. They are about keeping the POAM current, each of which needs documented evidence of due diligence and due care such as policies, standards, procedures, and configuration screenshots:
Reasonable objective evidence for an assessment is often subjective. The following examples of evidence to address NIST 800-171 R3 03.12.02 are sourced from the SCF Evidence Request List (ERL), available at https://securecontrolsframework.com/free-content/scf-download. These ERL artifacts are mapped to NIST 800-171 R3 03.12.02 through SCF controls. They establish a starting point for discussions on what an organization needs to have for evidence of due diligence and due care to withstand external scrutiny by an assessor or regulator.
Alongside these, keep the System Security Plan (SSP) narrative for 03.12.02.
With two (2) AOs mapping indirectly, two net new, and one with no clear mapping, 03.12.02 is a moderate lift centered on the update process. A realistic sequence:
How many assessment objectives does NIST 800-171 R3 03.12.02 have? NIST 800-171A R3 breaks 03.12.02 into five (5) assessment objectives. An assessor works through each one separately, so each needs its own evidence.
Which NIST 800-53 R5 control does NIST 800-171 R3 03.12.02 come from? CA-05.
How many Organization-Defined Parameters (ODPs) does NIST 800-171 R3 03.12.02 have? None (0). The requirement contains no bracketed assignment, so there is no organization-defined value and nothing for the DoD to specify.
Where does NIST 800-171 R3 03.12.02 sit in the NIST 800-171 R3 Kill Chain? Phase 5b, Document The CUI and/or FCI Environment. The Kill Chain is a phased model for sequencing R3 implementation, and it assigns this requirement to that phase.
03.12.02 Plan of Action and Milestones develops a POAM to track remediation and reduce vulnerabilities, and updates it from assessments, audits or reviews, and continuous monitoring. It maps from R2 3.12.2 with POAM development transitioning indirectly, while the audit and continuous-monitoring update triggers are net new. The recurring problem is a static, certification-only POAM. Build the POAM from real findings, and keep it current from all three sources.
Authoritative sources:
Authoritative sources:
This guide reproduces U.S. Government text from NIST 800-171 R3 and NIST 800-171A R3. It is educational, not legal or assessment advice. Last reviewed: 2026-09-22.
