In large-scale agile projects, product owners undertake a range of challenging and varied activities beyond those conventionally associated with that role. Using in-depth research interviews from 93 practitioners working in cross-border teams, from 21 organisations, our rich empirical data offers a unique international perspective into product owner activities. We found that the leaders of large-scale agile projects create product owner teams. Product owner team members undertake sponsor, intermediary and release plan master activities to manage scale. They undertake communicator and traveller activities to manage distance and technical architect, governor and risk assessor activities to manage governance. Based on our findings, we describe product owner behaviors that are valued by experienced product owners and their line managers.