They need both, but monitoring should not wait for the next review cycle. Reviews validate whether current access still makes sense, while monitoring catches the moment new permissions are created. In a complex directory, that combination is what stops fresh permission debt from becoming permanent before auditors or attackers find it.
Should Organisations Treat Monitoring and Reviews as the Same Control?
No. Access reviews and permission monitoring solve different problems in Active Directory, and one cannot substitute for the other. Reviews answer whether existing access still has a business justification at a point in time. Monitoring answers whether permissions changed, drifted, or expanded since that last attestation. In practice, the strongest posture is to run both against the same entitlement model, not to pick one and let the other lag.
That matters because directory risk is often cumulative. A role review can be clean on Monday and still be obsolete on Tuesday if a new group membership, delegated right, or privileged assignment appears outside the normal change path. Monitoring gives you the near-real-time signal; reviews give you the governance checkpoint.
What Each Control Catches in Active Directory
Permission monitoring is strongest at detecting fresh change: newly granted group membership, privileged role assignment, delegated rights, unexpected ACL changes, and other entitlement movements that may never wait for the next quarterly campaign. It is especially useful where administrative shortcuts, emergency access, or script-driven changes create rapid drift.
Access reviews are strongest at validating necessity. They tell you whether a user, admin, or service principal still needs a permission that already exists, and they help remove stale access that monitoring may simply record forever. If you only monitor, you can detect growth but still leave old excess untouched. If you only review, you can rationalise yesterday’s access while missing today’s exposure.
A practical way to think about this is lifecycle versus state. Monitoring tells you what changed; review tells you whether the current state is still defensible. In a directory with inherited rights, nested groups, and broad administrative delegation, the two views are complementary rather than interchangeable.
Why the Answer Changes at Scale
As Active Directory grows, the interval between entitlement creation and human review becomes the main risk window. That is where permission debt becomes permanent: access is added for speed, forgotten after the incident, and then carried forward as if it were normal. The Active Directory and Entra ID Hardening Guide is useful here because it frames privileged groups, delegation, and service accounts as control points that need continuous visibility, not just periodic inspection.
Monitoring also improves review quality. A review campaign is far more useful when reviewers can see what changed since the last cycle, which rights were added recently, and whether the entitlement came from a sanctioned workflow or an unexpected path. Without that context, reviewers tend to rubber-stamp large directories because the volume is too high and the evidence is too thin.
That is why the question is not really “which one first?” It is “which one is your early-warning system, and which one is your attestation layer?” In mature environments, monitoring feeds exception handling and review feeds cleanup. The result is a loop, not a one-off event.
Risk and Threat Considerations
Delayed reviews create a time gap that attackers and insiders can exploit. If a permission is granted and remains active until the next certification cycle, that right can be used for persistence, privilege escalation, lateral movement, or data access long before anyone notices. Monitoring reduces that blind window by surfacing unexpected permission growth as soon as it occurs.
Failure mechanism: Review-only programmes tend to validate access after the fact, while permission changes in Active Directory can happen continuously through delegated administration, nested groups, or automated provisioning. That gap allows excessive access to accumulate and persist.
Impact: The directory ends up with standing excess privilege, weaker accountability, and a larger blast radius when an account, group, or admin path is abused. The same gap also makes audit evidence less credible because the organisation can only explain access long after it changed.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
CIS Controls v8 and NIST SP 800-53 Rev 5 set the technical controls, while ISO/IEC 27001:2022 defines the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| CIS Controls v8 | CIS-5 — Account Management | Active Directory permission monitoring and access reviews both govern account and entitlement change. |
| Recommendation — Monitor account and entitlement changes continuously, then remove unnecessary access during scheduled reviews. | ||
| NIST SP 800-53 Rev 5 | AC-2 — Account Management | Active Directory reviews and monitoring both support ongoing account lifecycle and entitlement governance. |
| AU-6 — Audit Review, Analysis, and Reporting | Permission monitoring needs reviewable evidence and timely analysis of directory changes. | |
| Recommendation — Review accounts and privileges regularly and track changes so excess access is removed promptly. Analyze directory change events and alert on unexpected privilege movement. | ||
| ISO/IEC 27001:2022 | A.5.15 — Access control | The question is about governing access in Active Directory through both monitoring and review. |
| Recommendation — Define access control rules that combine entitlement review with ongoing change monitoring. | ||
Practitioner Guidance
What to prioritise: Treat monitoring as the faster control and reviews as the authoritative cleanup control. If you must sequence the work, start by monitoring the entitlements that can create the most damage, such as domain admin membership, privileged delegation, tier-zero groups, and service account rights.
What to verify: Make sure monitoring is tied to a complete entitlement inventory, otherwise you will detect changes on only part of the directory. Also verify that every review campaign can see recent permission deltas, not just the current snapshot, because change context is what turns a review into a decision.
Common mistake: Organisations often let quarterly reviews carry the whole burden and then assume a clean campaign means the environment is safe. That is too slow for Active Directory, where privilege can be created, inherited, or expanded between cycles without any human approval.
Practitioner takeaway: Use monitoring to catch permission creation immediately and reviews to retire unnecessary access deliberately. If one control is missing, the other will still leave you with either blind change or stale privilege.
Related resources from NHI Mgmt Group
- When should organisations prioritise NHI monitoring over more access approvals?
- When should organisations prioritise discovery over access reviews?
- When should organisations prioritise real-time fraud monitoring over batch reviews?
- When should organisations prioritise data access governance over more IAM roles and reviews?