Google Zanzibar is the singular authorization service that powers permissions and sharing across all Google properties, including Docs, YouTube, and Cloud IAM. Creating a consistent, global-scale authorization system that can process "more than 10 million client queries per second” is not a trivial task. The talk will cover how the paper lays out an engineer-friendly blueprint for building a highly scalable distributed system with flexible consistency guarantees. This talk will start with foundational knowledge of Relationship Based Access Control (ReBAC) and then cover the technical implementations behind Zanzibar - How Google solved for correctness, scale and speed. The presentation will cover the different APIs for interacting with the system and also a deep-dive into how the “New Enemy” problem was solved. The talk will conclude with how you can use open source tools to build authZ into your application.K