Project planning is subject to diminishing returns and contradictory demands. While management requires a comprehensive overview of activities, costs, and benefits, detailed planning for an uncertain future can be wasteful, as reality quickly catches up with the plan. Agile rolling wave planning is a multi-level, multi-horizon planning approach designed to address this challenge. This paper outlines the theoretical foundation and practical application of agile rolling wave planning during a ServiceNow implementation project. A systems thinking model of project uncertainty is presented, along with four fundamental counter strategies. Based on the model, it is demonstrated how agile rolling wave planning reduces uncertainty by providing relevant information and facilitates horizontal coordination between teams. A roadmap for AI-enabled project management software to support the method is outlined. Agile rolling wave planning techniques enable organizations to transition from risk to uncertainty management, applying agile principles beyond the software development realm.