Conclusions: so what have we learned?

The final chapter presents a summary of the key themes and insights from the Elgar Handbook as workshopped in Dublin in October 2023 and developed by the named authors. Health system resilience is a potent and useful concept which has shown a versatility and appeal across a range of health system crises. Nevertheless, it still needs to gain maturity with key challenges around understanding and measurement and the incorporation of power and equity in very different contexts. Furthermore, there is important mutual learning from the complex adaptive system research focus in low- and middle-income countries and the functional, economic approach in high-income countries. The Handbook highlights the nested nature of health system resilience and the importance of “response resilience” which evaluates how health systems cope with poor senior-level decision-making in a shock. In particular, key strategies for handling austerity are outlined. The authors also emphasise the importance of understanding and managing the interplay of shocks and of protecting disadvantaged groups throughout. The chapter also highlights innovative research methods (system dynamic modelling, realist reviews and scenario-based stress testing) which yield rich understanding. There is an exciting future for health system resilience research, to continue exploring issues around definitions, contextual influences, the value of data, the dynamic nature of crises and their effects, and the tension and complementarity between top-down and bottom-up approaches to building required capacity. This will be vital to inform strategies to meet the challenge of existing and future crises and to ensure better health system performance and wellbeing of populations.