McDonald's, the world's largest restaurant company, faced a challenge five years ago: transition over 100 markets from their own identity and access systems to a single, global system. As McDonald's embarked upon its new Accelerating the Arches strategic plan, it became clear that a global standard for identity and access was necessary to protect the brand and enable agility for the business. The McDonald's Global Identity and Access team's first step was to build repeatable processes that could be applied in compact deployment cycles in order to ensure market users were able to access new people programs being deployed globally. Since this onboarding was largely completed by the end of 2022, this session will include lessons learned on how to successfully deploy large scale, complex identity and access platforms. The second phase of the program, the modernization of the global platform in progress since 2023, has also yielded some insights and a number of questions and problems to solve, which will also be detailed.