What are the best scenarios for using Administrative Units in Microsoft 365? 
Administrative units (AUs) in Azure AD allow organizations to group users and resources based on specific criteria. This allows granular control over administrative tasks in Microsoft 365. Use administrative units to limit role scopes to ensure users access only the necessary resources while following the least privilege principle.
The least privilege principle is a security best practice that ensures users have only the minimum access necessary to perform their tasks. AUs make it easier to implement this principle by allowing administrators to restrict access to only the resources users need.
Administrative units (AUs) in Microsoft 365 can be utilized in the following scenarios:
Delegating Administrative Permissions: Leverage AUs to assign administrative tasks to specific departments or groups within your organization. This eliminates the need to grant global admin rights which limits access and responsibility to a specific set of users or resources.
Large Organizations with Multiple Regions: For organizations with branches or teams in various locations, AUs simplify the management of users, devices, and resources by region. This leads to more organized and secure administration.
Regulatory Compliance and Segregation: AUs provide a solution for businesses looking to segregate duties or restrict access to sensitive data by roles or departments. They provide granular permissions that align with these requirements.
Improved Security Control: Utilizing AUs enables you to restrict admin access to specific organizational units which minimizes the risk of unintended changes.
By leveraging administrative units in these ways, you can unlock their full potential. Still unsure how administrative units can benefit your organization? Here's a sample scenario to provide further clarity.
If an organization has offices in Seattle and Dallas, each with its own helpdesk, it may face challenges without administrative units (AUs). For instance, helpdesk staff in Dallas might be able to reset passwords for Seattle users. By using AUs, you can assign administrative rights specific to each office. This ensures that helpdesk teams manage users only within their own locations, without affecting the rest of the organization.