INTRODUCING
Actually Azure active directory B2B Collaboration still in public preview but this is one awesome services from Microsoft in azure active directory so you must know this.
Azure AD B2B collaboration lets you enable access to your corporate applications from partner-managed identities. You can create cross-company relationships by inviting and authorizing users from partner companies to access your resources. Complexity is reduced because each company federates once with Azure Active Directory and each user is represented by a single Azure AD account. Security is increased because access is revoked when partner users are terminated from their organizations, and unintended access via membership in internal directories is prevented. For business partners who don’t already have Azure AD, B2B collaboration has a streamlined sign-up experience to provide Azure AD accounts to your business partners.
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