The current mental healthcare system for people with serious mental illness is particularly fragmented, costly, and suboptimal for patients’ outcomes, which makes overarching, coordinating and evidence-based healthcare models particularly important. The metropolitan area of Hamburg is the research lab for complex healthcare models which include all diagnoses and all professional players and stakeholders in healthcare. Currently evaluated models by researchers of the MH-TRN are designed to address core problems of routine health care with a special focus on SMI, and show convincing effects in several central outcome domains. The major competence of the MH-TRN with regard to complex healthcare models is the involvement of patients and stakeholders from health insurances and policy, fostering sustainable implementation ensured by mental health economic evaluation and recommendation.