How should teams decide whether to use IAM, IGA, or both?

Why IAM and IGA Solve Different Parts of the Same Problem

Security teams often treat IAM and IGA as interchangeable, but they answer different questions. IAM is the control plane for authentication, provisioning, and access enforcement. IGA is the governance plane that asks whether access is justified, reviewed, and still appropriate. That distinction matters because access can be technically valid and still be operationally wrong. NHI Management Group has documented how exposure persists when secrets and service accounts are not governed with the same discipline as human access, and the 2024 Non-Human Identity Security Report found that 88.5% of organisations say their non-human IAM practices lag behind or only match human identity practices.

That gap shows up in real incidents: JetBrains GitHub plugin token exposure and Schneider Electric credentials breach both illustrate how authentication alone does not prove access was justified, reviewed, or constrained. For teams formalising this distinction, the NIST Cybersecurity Framework 2.0 is a useful baseline because it separates identity control from governance and oversight. In practice, many security teams discover the IAM versus IGA gap only after access has already been over-granted, not through a planned design review.

How Teams Decide What to Put in IAM, IGA, or Both

The practical test is simple: if the task is to create, prove, or enforce access in the moment, it belongs in IAM. If the task is to explain, certify, or continuously validate why that access exists, it belongs in IGA. Mature programmes usually need both because secure access is not the same as justified access. IAM establishes the account, credential, policy, and session control. IGA adds review workflows, exception handling, separation-of-duties checks, and audit evidence.

For non-human identities, that split becomes more important because access patterns are often machine-generated, short-lived, and easy to over-provision. NHI Management Group guidance highlights that NHIs outnumber human identities by 25x to 50x in modern enterprises, while only 5.7% of organisations have full visibility into their service accounts. That makes IGA essential for inventory, ownership, and attestation, even when IAM is already provisioning access automatically. The NIST framework reinforces this operational split by separating identity proofing and access enforcement from governance and continuous risk review.

• Use IAM for authentication, token issuance, key rotation, provisioning, and enforcement at request time.
• Use IGA for access recertification, approvals, policy exceptions, ownership tracking, and audit trails.
• Use both when access must be granted quickly but still justified, especially for service accounts, API keys, and privileged workloads.
• Prefer IAM-only for low-risk, heavily automated access paths that do not require periodic business review.

Where teams get this wrong is assuming a provisioning workflow is the same thing as governance. It is not. IAM can create access in seconds, but without IGA the organisation may never know whether that access still has a business owner, a valid purpose, or an acceptable risk level. These controls tend to break down in multi-cloud and hybrid environments because identity sprawl makes ownership and certification drift faster than manual review cycles can keep up.

Common Edge Cases and the Tradeoffs That Matter

Tighter governance often increases process overhead, so organisations have to balance speed against assurance. That tradeoff is real, especially when platform teams want automated access delivery while security teams want documented justification. Current guidance suggests that the answer is not to choose one tool category permanently, but to assign the control based on risk, privilege, and lifecycle length. For example, a short-lived CI/CD token may need strong IAM controls but limited IGA review, while a persistent database admin account needs both issuance control and recurring certification.

One common edge case is ephemeral access. If access expires quickly and is automatically revoked, the governance burden may shift from manual recertification to policy design and logging. Another is delegated administration, where a business team can request access but should not be able to approve its own privilege. In those cases, IGA should enforce review paths while IAM enforces the entitlement itself. The 2024 Non-Human Identity Security Report shows why this matters: 59.8% of organisations value dynamic ephemeral credentials, which is a strong signal that static access models are already under pressure.

For teams building a control strategy, the safest default is to treat IAM as necessary but not sufficient. If an organisation cannot answer who approved access, who owns it, and when it must be reviewed, then IGA is not optional. That is especially true in environments with secrets exposure patterns like Azure Key Vault privilege escalation exposure, where the issue is not merely whether access works, but whether it should exist at all.

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