Implementing Zero Trust: How to Operationalize NSA Guidelines
Published February 26, 2026
Mikella Marley Content Marketing Manager
Nine out of ten security leaders agree that Zero Trust is key for enhancing overall security posture, yet 88% of CISOs have experienced significant challenges in their Zero Trust implementation attempts. In other words, there’s a gap between cybersecurity best practices and real-world enforcement.
The National Security Agency (NSA) aims to bridge this divide with its Zero Trust Implementation Guidelines (ZIGs). Released in January of 2026, Phase One and Phase Two of the NSA’s multi-part guidelines translate Zero Trust into dozens of concrete, measurable activities, like enforcing MFA, implementing network segmentation, and leveraging automation for dynamic policy enforcement.
The ZIGs give security teams a blueprint for building operational discipline around Zero Trust. As the NSA guidelines become central to audits and broader enterprise security discussions, this comprehensive breakdown explores key themes embedded in the NSA’s ZIGs and best practices for successfully implementing Zero Trust.
What Are the NSA’s Zero Trust Implementation Guidelines?
The NSA’s ZIGs are designed to assist organizations with incorporating Zero Trust (ZT) principles into their processes, enabling them to hit benchmarks outlined in complementary frameworks, architecture guides, and maturity models, including:
- National Institute of Standards and Technology (NIST), Zero Trust Architecture Special Publication (SP) 800-207
- The Cybersecurity and Infrastructure Security Agency (CISA) Zero Trust Maturity Model
- The NSA Zero Trust Reference Architecture (ZT RA)
The ZIGs provide a structured approach for organizing Zero Trust activities spanning five modular phases: Discovery, Phase One, Phase Two, Phase Three, and Phase Four.
While the current guidelines include only the first three phases, they encompass 91 activities designed to bring organizations to a “target level” of Zero Trust maturity, according to the NSA – phases three and four will include 61 additional activities for advanced-level maturity.
Accelerating Zero Trust: 4 Best Practices the ZIGs Quietly Codify
While the NSA’s ZIGs are broken down into distinct capabilities and activities, they collectively signal a handful of takeaways that move Zero Trust from aspiration to built-in reality.
1. Assume Breach and Limit Blast Radius by Design
“Assume breach” is a core tenet of Zero Trust; the ZIGs make it a structural principle. Activities around segmentation, internal access governance, and enforcement points all converge on a single outcome: limit lateral movement to minimize the impact of a breach.
Trust should not implicitly extend across the environment, and communication between systems must be explicitly governed. The goal is not simply to prevent intrusion but to ensure that if a compromise occurs, it is contained. As a result, cyber resilience is embedded in the network architecture.
2. Extend Least Privilege Inside the Network with Granular Access Controls
The ZIGs push the principle of least privilege past login, applying granular access controls to every connection – even internal ones. Privileged access paths and system-to-system communications must be explicitly allowed with trust decisions evaluated at defined enforcement points, not just at login.
By enforcing granular rules any time identities, devices, and workloads attempt to communicate, organizations can truly operationalize the “never trust, always verify” Zero Trust principle.
3. Continuous Enforcement Beats Static Configuration
Zero Trust is an operational practice, not a finish line – that means one-and-done controls inevitably fall short. Modern networks are dynamic; security policies should be, too.
The ZIGs explicitly point out that activities can be implemented concurrently and tailored to an organization’s individual needs. But these aren’t one-time milestones, they’re the first iteration in a new routine – enforcement must adapt.
Static rules inevitably leave gaps as networks evolve and behavior changes. Security teams must approach Zero Trust as a continuously evaluated condition rather than a checklist.
4. Automation Makes Zero Trust Scalable
Leveraging automation is the surest way to align with the NSA’s ZIGs without expanding operational overhead. Reducing standing access, maintaining segmentation boundaries, and ensuring policies reflect real communication patterns requires consistency – automation reduces policy drift and the risk of human error, allowing organizations to enforce least privilege without expanding headcount proportionally.
Operationalizing the ZIGs: Priorities for Implementing Zero Trust
Across Phase One and Phase Two, the NSA’s Zero Trust Implementation Guidelines outline 90+ activities mapped to core Zero Trust pillars. Some key elements of the NSA’s ZIGs relate to dynamic policies, granular access control, end-to-end visibility, and tight coupling of identity and network enforcement.
| ZIG Domain | Activity, Capability, or Direction | What It Means for Security Teams | How to Achieve It |
|---|---|---|---|
| Identity | Enforce MFA on privileged access | Admin and high-risk pathways need an additional layer of security throughout the network (not just at login) | Network-layer MFA on privileged ports & protocols |
| Identity | Reduce standing access | Identity-aware access rules should be tied to real traffic | Granular access controls tied to identity enforced on the network layer |
| Identity | Continuous authentication | Trust should be re-verified but not disruptive | Dynamic, context-aware access policies and enforcement across the network |
| Device | Inventory and posture awareness | Know what’s connecting to enforce accurate policies | Tie asset discovery to network traffic visibility for accelerated rule creation |
| Device | Comply-to-connect (C2C) | Risky devices should be blocked from connecting | Implement policy-based access gating |
| Network | Limit lateral movement with granular segmentation | Isolate apps, workloads, and services to prevent spread after a breach | Automatically isolate and quarantine any compromised asset or identity, blocking east-west and north-south movements with identity-based microsegmentation |
| Network | Default-deny internal access | Remove implicit trust inside the network and explicitly govern east-west traffic | Enforce fine-grained access policies to limit internal communications |
| Network | Continuous enforcement | Policies must adapt as context changes | Adaptive, behavior-driven segmentation |
| Visibility | Map traffic flows | Enforcement requires understanding dependencies | Real-time traffic visibility and behavior-based policy enforcement |
| Automation | Reduce manual workload and minimize humans in the loop | Proactively avoid human error and scalability struggles | Automation-first policy lifecycle with self-maintaining enforcement |
| Network & Identity | Unified policy decisions | Identity and network activities should not be siloed | Identity-aware network controls that evaluate identity, device, and context |
| Incident Response | Faster recovery | Containing breaches quickly is key to continuity | Proactively shrink blast radius to ensure the business stays operational during a breach and recovery isn’t needed |
| Resilience | Assume breach | Blast-radius reduction should be structural | Build containment into the network architecture |
How to Put Zero Trust Implementation Guidelines in Practice
With a cumulative view of key ZIG activities, security teams gain an actionable strategy for implementing Zero Trust:
- Tie access controls to identity and continuously verify: Protect privileged paths and sensitive communications with contextual, policy-driven enforcement – trust must be evaluated anywhere access happens.
- Eliminate implicit internal trust: Adopt default-deny principles for east-west traffic, where every communication is explicitly governed and continuously evaluated.
- Architect containment with granular segmentation: Design microsegmentation boundaries that meaningfully limit how far a compromise can travel, confining blast radius through structure.
- Unify policy decisions across network and identity: Access decisions should reflect who is requesting access, from what context, and to which asset. Zero Trust breaks down when these signals operate in silos.
- Let real network behavior drive enforcement: Real-time traffic insights – not best guesses or likely scenarios – should inform policy creation and refinement.
- Automate to sustain Zero Trust at scale: Manual policy management does not scale. Security coverage must adapt as environments evolve, minimizing drift and reducing operational burden.
Accelerate Zero Trust Implementation with Zero Networks
Zero Networks makes it easy to hit the Zero Trust goalposts outlined in the NSA’s ZIGs. By delivering comprehensive identity-based microsegmentation where identity governs reachability at the network layer and adaptive, granular access controls prevent lateral movement by default.
By tightly coupling identity and network enforcement, securing privileged access with just-in-time MFA, and proactively eliminating always-on access paths, Zero secures every axis of network traffic and enables a resilient Zero Trust Architecture.
Find out how you can simplify Zero Trust implementation and fast-track your organization’s journey through the NSA’s guidelines – request a demo.