Azure AD External collaboration settings govern who can bring guests into the tenant. The SC-300 content specifies: “External collaboration settings let you control who can invite guests (Anyone, Members, Guests, or Only admins and users in the Guest Inviter role) and whether guests can invite.” It also highlights: “To restrict guest invitations to administrators or designated inviters, configure External collaboration to ‘Only admins and users in the Guest Inviter role’ and disable guest-to-guest invitations if required.” Because the problem states that “Anyone in the organization can invite guest users, including other guests and non-administrators,” the remediation is to tighten External collaboration settings so only approved roles (e.g., Global admins, Guest Inviter, or specific administrators) can invite. Access reviews address periodic entitlement verification, Conditional Access enforces sign-in/session policies, and Continuous Access Evaluation relates to token lifetime/signal-based revocation; none of these change who can send guest invitations. Adjusting External collaboration settings directly resolves the issue and aligns with the requirement that “only users that are assigned specific admin roles can invite guest users.”