Managing interdependencies in a cross-organizational project, especially one that affects multiple business units and shares resources with other projects, requires a coordinated approach. The PMBOK Guide highlights the importance of identifying and engaging stakeholders who can influence the project's outcomes1. In this scenario, program managers are typically responsible for overseeing the program's overall direction and managing dependencies across projects within the program2. Consulting with program managers first can provide a comprehensive view of the program's objectives, resources, and constraints, which is crucial for effectively managing interdependencies. References: Stakeholder Management - Project Management Institute; Project Stakeholder Management According to the PMBOK12.