This document provides an overview of Microsoft Azure Active Directory (Azure AD). Azure AD is a cloud-based identity and access management solution that can be used as a standalone directory or integrated with an existing on-premises Active Directory. It allows single sign-on access to SaaS applications and stores user identity data in the cloud. Premium versions of Azure AD provide additional features like self-service password reset and security reports. Administrators can manage users, groups, applications and domains through the Azure AD portal.