Crises and complexity: how can we make health interventions succeed?

The end of the COVID-19 global health emergency presents an opportunity to reflect on actions needed to enhance the effectiveness of responses to any future shocks. We highlight critical areas requiring attention from researchers and research commissioners to enhance the identification and adoption of 'good value' interventions, and we discuss the complexities of evidence-informed decision-making across multiple sectors, the evolving role of modeling, and the need for improved stakeholder engagement and institutional coordination to effectively address interconnected health and policy challenges. We conclude the commentary by making a set of related recommendations to support intervention identification and implementation. Researchers, policymakers, and other key stakeholders should: renew efforts to step out of silos and to develop methods and frameworks that link and synthesize evidence from multiple sources and perspectives, to support planetary health goals and the 'One Health' concept; support more research into understanding the constraints to adopting interventions regarded as good value for money, to enhance evaluation methods ex ante and to better inform systems and stakeholders of the implementation requirements; and maintain an ongoing commitment to equitable research partnerships to ensure that evidence use is relevant for the target settings.