Zero Trust is an alternative security model that addresses the shortcomings of failing perimeter-centric strategies by removing the assumption of trust. With Zero Trust there is no default trust for any entity—including users, devices, applications, and packets—regardless of what it is and its location on or relative to the corporate network. This paper discusses the need for a Zero Trust approach to network security, how the Palo Alto Networks® next-generation security platform delivers on these requirements, and provides guidance on how to progressively migrate to a Zero Trust architecture.