Cross‐sector collaboration combining public (non‐commercial) and private (commercial) organisational orientations is considered an advantageous and dynamic strategic approach to shared value creation and co‐creative innovation in disruptive operational environments of media industries. However, cross‐sector collaboration features inherent complexities and organisational tensions due to the fundamental differences between the actors’ strategies and operational models. This article explores organisational tensions and dualities in media work in the cross‐sector collaboration of media clusters. The qualitative case study examines the development of the management approach and practical operations of the Finnish media cluster Mediapolis, which aims to produce value, especially through collaborative content and concept innovation. The case study builds on extensive empirical material collected since the Mediapolis project started in 2011 until 2018. The analysis focuses on the management of complexities and organisational tensions in implementing collaborative strategies at Mediapolis, as well as managing the shared operations and work of the cluster. The results reveal tensions between the core dualities in developing Mediapolis as a collaborative arrangement between the participating organisations in practice, despite shared strategic‐level aspirations. The findings elaborate on the dynamics of different organisational orientations and business logics, discrepancies between visionary planning and practical actions, and opposing organisational interests and strategies as sources for organisational tensions in collaborative contexts. The article contributes to both the theoretical and practical knowledge on organisational tensions and their management in cross‐sector collaboration in media cluster development and provides implications for managing respective complexities in media work.