What Is Zero Trust Security? A Guide for IT Teams

For decades, enterprise security operated on a simple assumption: Everything inside the network perimeter is trusted. Employees sat behind firewalls, connected to on-premises servers, and accessed resources over a corporate VPN. The perimeter was the defense.

That model had to evolve. Cloud adoption, remote work, SaaS sprawl, and increasingly sophisticated attackers have dissolved the perimeter entirely. In our 2026 security forecast, Dashlane CTO Fred Rivain predicted that 2026 would mark the collapse of the traditional network perimeter, and the data agrees. The Verizon 2025 Data Breach Investigations Report found that 68% of breaches involved a human element, with credential theft and phishing leading the way.

Zero trust security is the answer the industry has converged on. It’s now a mandate for U.S. federal agencies under executive order, a board-level priority at enterprises globally, and an operating principle that every IT team needs to understand.

This guide explains what zero trust security is, how it works, its three core principles, and how it applies to the most commonly overlooked element of any zero trust strategy: Credential management.

Zero trust security is a cybersecurity framework built on the principle of "never trust, always verify." Rather than assuming that users, devices, and systems inside a network are safe by default, zero trust treats every access request as potentially hostile, regardless of where it originates.

The concept was coined by Forrester Research analyst John Kindervag in 2010 and has since been adopted by NIST (National Institute of Standards and Technology), the U.S. Department of Defense, and virtually every major enterprise security framework. In 2022, President Biden's executive order on cybersecurity made zero trust architecture a requirement for all U.S. federal agencies.

In practical terms, zero trust means:

The traditional perimeter model assumed that your office network was secure. Once inside, systems communicated freely. But consider how enterprise work actually happens:

In this environment, the network perimeter is meaningless. An attacker who compromises a single employee's credentials—through phishing, password reuse, or credential stuffing—can move laterally through systems that implicitly trust anyone who is “in.”

Zero trust closes that gap. It assumes breach from the outset and designs security controls accordingly.

NIST's zero trust architecture (SP 800-207) and Microsoft's zero trust model both organize the framework around three foundational principles. Understanding these is essential for any IT team planning a zero trust rollout.

Never grant access based on location or network membership alone. Every access request must be authenticated and authorized based on all available data points: Identity, device health, location, service requested, and behavioral signals.

In practice, this means:

Grant users, apps, and services only the minimum permissions required for their specific function and for only as long as they need it. This principle limits the blast radius of any breach: A compromised account can only access what it was permitted to access, not the entire environment.

In practice, this means:

Design your security posture as if an attacker is already inside. This is realism, not pessimism. The ”assume breach” principle drives you to minimize lateral movement, encrypt data in transit and at rest, and build monitoring and response capabilities that detect anomalous behavior quickly.

In practice, this means:

If zero trust is built on verifying identity at every access point, then the tools used to manage, store, and authenticate with credentials are the operational backbone of any zero trust strategy.

Yet, credentials remain the most commonly neglected element of enterprise security programs. Consider:

An enterprise password manager closes these gaps directly. It ensures that every employee uses strong, unique, auto-generated credentials for every account; that credential sharing is encrypted and auditable; and that offboarding immediately revokes access.

Dashlane's zero-knowledge architecture aims to ensure that encrypted credentials are never accessible to Dashlane or any third party, even in a breach. This aligns directly with the ”assume breach” principle: Even if systems are compromised, credential data remains encrypted and unreadable.

Single sign-on (SSO) is a pillar of most enterprise zero trust strategies. It centralizes identity verification and reduces the number of credentials in use. However, as we explain in our post on why SSO alone isn't enough, SSO can’t cover the long tail of SaaS apps, internal tools, and web services that fall outside the SSO umbrella.

The combination of SSO and an enterprise credential manager is what actually delivers zero trust at the credential layer. SSO and a credential manager work better together: SSO handles core apps with centralized identity enforcement, while the credential manager secures everything else with strong, unique passwords and encrypted sharing.

Zero trust is a journey, not a switch you flip. Most organizations implement it incrementally across four phases:

[Phase 1] Identity and credentials: Deploy MFA site-wide. Implement an enterprise password manager. Audit and rotate all shared credentials. Establish a credential offboarding process.

[Phase 2] Device and endpoint: Enforce device health policies. Require managed devices for access to sensitive systems. Deploy EDR across all endpoints.

[Phase 3] Application access: Integrate SSO with all core apps. Implement RBAC. Audit app access permissions. Revoke excessive privileges.

[Phase 4] Network micro-segmentation: Segment your network by sensitivity and function. Implement east-west traffic controls, which manage, monitor, and secure data flowing laterally between servers, virtual machines, or containers within a data center or cloud. Deploy SIEM for continuous monitoring and anomaly detection.

Start with Phase 1. Identity and credentials are the most common initial attack vector and the most actionable starting point for most organizations. A properly deployed enterprise password manager with MFA enforcement and SSO integration delivers immediate, measurable zero trust improvements, often within weeks.

Zero trust rollouts frequently stall or fail because of predictable implementation errors. Here are the most common and how to avoid them:

Dashlane is built around the same principles that define zero trust security.

Verify explicitly: Confidential SSO & Provisioning integrates with Okta, Microsoft Entra ID, Google Workspace, and any SAML 2.0 IdP. Employees verify identity using corporate SSO credentials, no master password required. AI phishing alerts and FIDO2 security key support add additional verification layers.

Least privilege: Role-based access controls let admins define permissions at the user, group, and vault level. Secure sharing enables credential access without exposing the underlying password. SCIM provisioning automates immediate access revocation during offboarding.

Assume breach: Patented zero-knowledge architecture aims to ensure that even if Dashlane’s infrastructure is compromised, attackers shouldn’t be able to access stored credentials or secrets. Activity logs feed directly into SIEM systems. Dark Web Monitoring and Credential Risk Detection surface compromised credentials before attackers can use them.

Zero trust security means your organization never automatically trusts any user, device, or system, even those already inside your network. Instead, every access request is verified at the time it’s made, based on identity, device health, and context. The guiding principle is ”never trust, always verify.”

The three core principles of zero trust are: (1) Verify explicitly: Authenticate and authorize every access request using all available signals; (2) Use least privilege: Grant only the minimum access necessary; and (3) Assume breach: Design security as if an attacker is already present.

Zero trust is a strategic framework, not a specific product. It’s implemented using a combination of tools, such as identity providers, MFA solutions, endpoint management, and credential managers, aligned around the principle of never granting implicit trust.

An enterprise password manager enforces several core zero trust principles: It ensures every employee uses strong, unique credentials (verify explicitly); it restricts access to only the credentials each employee needs (least privilege); and its zero-knowledge architecture means credentials remain encrypted even in a breach scenario (assume breach). Integration with SSO and automated deprovisioning further strengthen the zero trust posture.

A VPN creates an encrypted tunnel that grants broad network access once a user authenticates, essentially extending the perimeter to include remote users. Zero trust replaces the perimeter model entirely: Instead of trusting all traffic within a network segment, it requires continuous verification at the app and resource level. Zero trust provides more granular, less exploitable access control than a VPN.

U.S. federal agencies are required to implement zero trust architecture under the 2022 executive order on cybersecurity and subsequent CISA guidance. While not universally mandated in private sector compliance frameworks, zero trust principles are increasingly referenced in NIST guidelines, SOC 2, ISO 27001, and industry-specific regulations. Organizations subject to CMMC (defense contractors) have explicit zero trust requirements.