This blog was originally published by 360 Visibility here

Conditional Access in Microsoft 365: 7 Practices for Smarter Security

Not every sign-in deserves the same level of scrutiny. For example, an employee signing in from a managed laptop they’ve used every day for months is very different from someone attempting to access sensitive company data from an unfamiliar device in another country.

Yet a traditional username-and-password model can treat both scenarios the same way.

That’s where Microsoft Conditional Access comes in because it allows organizations to make access decisions based on the context surrounding a sign-in. It can consider factors such as:

– Who is signing in
– What device they’re using
– Where they’re signing in from
– Which application they’re accessing
– Whether the device meets security requirements
– Whether Microsoft has detected signs of risk

Based on those signals, an organization can allow access, block it, or require additional verification.

The result is a more adaptive approach to security: stronger controls when the risk is higher, and fewer unnecessary interruptions when the risk is low.

Here are seven best practices for getting it right.

What Is Conditional Access?

Conditional Access is Microsoft’s policy-based approach to controlling access to applications and resources.

Think of it as a set of rules that answers a simple question: under what circumstances should this user be allowed to access this resource?

For example, an organization might create a policy that:

1. Requires MFA when a user signs in from an unfamiliar location
2. Blocks access from selected countries
3. Prevents access from non-compliant devices
4. Requires stronger authentication for administrators
5. Restricts access to sensitive applications based on risk
6. Allows trusted users on managed devices to sign in with fewer interruptions

This is fundamentally different from applying one security rule to everyone.

The goal isn’t to make access difficult, it’s to make risky access difficult.

That distinction matters. Poorly designed Conditional Access policies can create frustration, increase help desk requests and encourage employees to look for workarounds. Well-designed policies can strengthen security while remaining largely invisible to users during normal work.

7 Best Practices for Implementing Conditional Access

1. Start With MFA, but Don’t Stop There

Multi-Factor Authentication should be one of the first controls organizations consider when building a Conditional Access strategy.

MFA adds another layer of verification when a password alone isn’t enough to establish someone’s identity.

Conditional Access allows organizations to apply MFA based on specific circumstances, such as user risk, sign-in risk, application sensitivity or other defined conditions.

Privileged accounts should generally receive particularly strong protection, because compromising an administrator account can give an attacker access to significantly more of the environment.

2. Protect Administrative Accounts First

Not every account represents the same level of risk.

A compromised administrator account can potentially have far greater consequences than a compromised standard user account. That makes privileged identities an obvious place to start.

Consider stronger controls for administrative accounts, such as:

– MFA for every sign-in
– Access from managed or compliant devices
– Strong authentication methods
– Additional restrictions based on risk or location
– Separate administrative accounts for privileged tasks

This is one area where security teams should resist the temptation to make policies convenient.

If an account can change security settings, create users or access sensitive resources, it deserves a higher level of protection.

3. Make Device Health Part of the Access Decision

An employee could have legitimate credentials but be attempting to access company resources from an outdated, compromised or unmanaged computer.

Conditional Access can work with Microsoft Intune and device compliance policies to determine whether a device meets your organization’s security requirements.

Depending on the environment, those requirements could include:

1. Current operating system versions
2. Disk encryption
3. Endpoint protection
4. Security updates
5. Device enrollment
6. Defined compliance policies

This creates a stronger relationship between identity security and endpoint security.

4. Use Location and Risk Signals Carefully

Location can provide useful context, but it shouldn’t become a blunt security tool.

For example, if an organization operates exclusively in North America and a user’s account suddenly generates a sign-in from another region, that may warrant additional scrutiny.

Conditional Access can be used to:

– Block access from selected locations
– Define trusted network locations
– Require additional authentication for unfamiliar locations
– Combine geographic signals with other risk indicators

But location alone shouldn’t necessarily determine whether someone is legitimate.

Employees travel. VPNs exist. Cloud services operate across borders.

The strongest policies combine multiple signals rather than assuming that geography tells the whole story.

5. Apply Least Privilege

Conditional Access controls how users access resources, but organizations also need to consider what users can access in the first place.

The principle of least privilege means giving users only the access they actually need to do their jobs.

That limits the potential damage if an account is compromised.

For example, someone working in finance may need access to financial applications and files, but that doesn’t mean they should automatically have access to every SharePoint site, application or administrative function in the organization.

Conditional Access works best when it’s part of a broader identity and access strategy that considers:

Who should have access?
What should they have access to?
Under what conditions should they be allowed to access it?

6. Test Policies Before You Enforce Them

One of the easiest ways to create a security problem is to implement a new policy without understanding its impact.

A Conditional Access policy that looks sensible on paper can behave very differently once it’s applied to a real organization with remote employees, legacy applications, contractors, executives and multiple device types.

Microsoft provides tools such as report-only mode that allow organizations to evaluate the potential impact of policies before fully enforcing them.

Use that opportunity.

Test policies with different users and scenarios. Look for:

1. Unexpected access blocks
2. Applications that don’t behave as expected
3. Users who would be unnecessarily prompted
4. Conflicts between existing policies
5. Administrator access issues
6. Legacy application dependencies

The goal is not simply to make the policy work.

It’s to make sure the policy works without creating a new operational problem.

7. Review Policies Regularly

Your Microsoft 365 environment isn’t static.

Employees join and leave. Devices change. Applications are added. People travel. Business operations evolve. And the threat landscape certainly doesn’t stand still.

Conditional Access policies should therefore be reviewed regularly.

Look at:

1. Authentication and sign-in activity
2. Policy results
3. Failed access attempts
4. Risk detections
5. User and help desk feedback
6. Changes to applications and devices

A policy that made sense two years ago may no longer make sense today.

Security policies should evolve with the organization they protect.

Common Conditional Access Mistakes

Even organizations with well-intentioned security strategies can run into trouble with Conditional Access.

Applying blanket policies

A single policy applied to everyone may be easy to manage, but it can create unnecessary friction.

Different users, applications and levels of risk may require different controls.

Forgetting emergency access accounts

Organizations should maintain carefully secured emergency or “break glass” accounts that can be used if normal authentication controls become unavailable or an administrative account becomes inaccessible.

These accounts should be protected, monitored and reserved for genuine emergencies.

Overlooking legacy applications

Some older applications may not support modern authentication methods. Identify these dependencies before introducing policies that could prevent legitimate access.

Making policies too complicated

More policies don’t automatically mean better security.

A complicated collection of overlapping rules can be difficult to understand, troubleshoot and maintain.

The objective should be clear, purposeful policies that address specific risks.

Forgetting the user experience

Security controls affect real people.

If employees are constantly challenged with unnecessary authentication prompts, they may become frustrated or start ignoring security warnings.

Good Conditional Access design considers both security and usability.

Conditional Access Is a Foundation for Zero Trust

Zero Trust starts with a straightforward principle: Never assume access should be trusted. Verify it.

That doesn’t mean asking employees to prove their identity every five minutes. It means making access decisions based on relevant signals rather than assuming that a user is safe simply because they’ve already logged in or are connected to a corporate network.

Identity, device, application, location and risk can all contribute to that decision.

This becomes increasingly important as organizations move more of their operations into the cloud and adopt tools such as Microsoft Copilot and other AI-enabled applications.

The more business data employees can access from anywhere, the more important it becomes to understand who can access that data, from where, using what device and under what conditions.

For organizations using Microsoft 365, it’s an important part of building a stronger identity and access strategy. And like any security control, its effectiveness depends on how thoughtfully it’s designed, implemented and maintained.

Need a Closer Look at Your Microsoft 365 Security?

If your Conditional Access policies have grown organically over time, or you’re not sure whether your current configuration is providing the protection your organization needs, a security assessment can help.

360 Visibility works with organizations across Canada and the US to assess and strengthen Microsoft 365 environments, including identity and access controls, endpoint security, data protection and broader security policies.

A good starting point is a Microsoft Security Score assessment, which can help identify opportunities to strengthen your organization’s security posture.