Background <p>Hindered by staff shortages, high workloads and rising waiting lists, mental healthcare services across Europe struggle to provide accessible, appropriate, and timely care for those who need it. In the past, governments tried to tackle large-scale issues in mental healthcare with profound policy changes, such as deinstitutionalization, decentralization and marketization. In the Netherlands, where mental healthcare is also under pressure, many policymakers and other influential stakeholders believe that policy changes aimed at stimulating collaboration between providers, third-party payers and other domains are a solution to the increasing challenges. This research analyses how a collaborative logic unfolds in a complex sector dominated by a market logic.</p> Methods <p>By analyzing policy documents and conducting interviews with representatives of healthcare organizations and health insurers, we explored both the systssemic and cultural barriers that challenge collaboration in mental healthcare.</p> Results <p>Findings show that, while collaboration is framed as a key strategy to resolve issues in mental healthcare, the entrenched market logic has fostered negative perceptions and lasting mistrust between mental healthcare stakeholders. These perceptions make collaboration difficult.</p> Conclusion <p>Challenges related to collaboration are not only systemic or financial in nature but are deeply rooted in belief systems, norms and values. A fundamental shift in these areas is essential to foster a more cooperative practice in mental healthcare.</p>