In this AWS re:Invent 2023 session, experts discuss best practices for operating on AWS at scale. They cover laying the foundation with multi-account strategies, centralizing governance, and streamlining operations. Key topics include defining operating models, aligning them with multi-account strategies, and using AWS Control Tower for centralized management. The speakers also demonstrate how to use AWS Systems Manager for automation and AWS AppConfig for feature flags to improve resilience. A real-world case study from Itaú Unibanco highlights their journey in implementing these practices, including challenges faced and lessons learned in scaling their AWS environment. The session provides valuable insights for organizations looking to optimize their AWS operations and achieve efficient management of mission-critical applications.