Climate change poses both the largest threat and the biggest opportunity for the future of global health. The health sector's ability to sustain the health of communities and effectively respond to the impacts of climate change relies on the resilience of our health systems and their ability to deal with shocks and stressors. The COVID-19 pandemic has made evident how interconnected our governing systems are as the world experiences the consequences of a major shock to health systems in high-income countries and low-income and middle-income countries. The 26th UN Climate Change Conference of Parties (COP26) in Glasgow that occurred in early November, 2021, along with any future Conference of Parties (COP), will shape global commitments for climate action and offers an important opportunity for the inclusion of health policy and systems research (HPSR), which aims to understand how health systems can adapt and respond to climate challenges.COVID-19, like climate change, is amplifying existing systemic vulnerabilities and inequalities. The HPSR community has recognised this opportunity to help transform our health systems to be resilient, socially just, and equitable. At the same time, the HPSR community is being called on to focus on the impending impacts that climate change will have on health systems, especially in low-income and middle-income countries that are more vulnerable to climate risks, whose systems are already overburdened, and whose governance structures are complex. HPSR literature acknowledges the importance of building resilient health systems, especially in relation to shocks resulting from climate-related risks that pose a threat to the governance of health systems.In addition to core functions and infrastructures of health systems (eg, information systems, financing mechanisms, and health workforce), to build and sustain resilience of health systems particular attention is required to governance at multiple levels, which is influenced by the values of decision-making actors. Crisis response (including climate crisis) is typically dominated by humanitarian response mechanisms, which do not adequately engage with or consider local governance structures. This matter has become abundantly clear in the recent convergence of zoonotic pandemics (eg, Ebola, COVID-19) and the climate crisis, and has generated discourse on the need to rethink humanitarian responses. It is necessary to reframe the approach to health governance to recognise the mutual interdependencies of countries and communities and to reconfigure decision-making to put equity, justice, and local voices at the heart of crisis response. If health systems are to be truly climate-resilient, they need to respond to these considerations. The HPSR community has long recognised the importance of people-centered health systems. There is a slowly emerging evidence base on how health systems can be more sustainable and resilient to shocks when governance and system structures are locally co-designed, integrate local knowledge, and equitably partner with community-embedded staff. Adaptation to protect communities was a central focus point of COP26, as it will also be for COP27, within which building resiliency is a key action, but it is not yet well defined.The HPSR community now has a crucial opportunity—and an important obligation—to develop the evidence base to inform how to build transformed and reconfigured climate-resilient health systems. This research can further support nations in two areas: (1) to develop and improve their national determined contributions, national adaptation plans, and health national adaptation plans; and (2) to generate accountability tools for governance of decisions and interventions that strengthen the health system against climate risks in ways that support local initiatives. In generating this new, transformational evidence base, the HPSR and climate change research communities must work together on making health systems resilient to climate change, before, during, and after COP26, and can do so by building on nascent existing platforms (eg, the Climate Resilient Health Systems Initiative under the Adaptation Action Coalition).Global cross-sector governance is challenging.2, 3 Nevertheless, the COP's intergovernmental structure provides an ideal convening opportunity for member states to share and critique the evidence that has supported the development and enhancement of existing policies and strategic plans, such as national adaptation plans. Importantly, COP's intergovernmental structure can facilitate the sharing of accountability tools, lessons learned, and civil society and stakeholder engagement strategies that can support the transformational development of climate-resilient health systems. COP policy negotiations can ensure that climate financing mechanisms support research on development of climate-resilient health systems, to secure human health into the future.HSPR stakeholders should work with COP constituents, especially before COP27, to critique the state of current evidence, share crucial knowledge on lessons learned for working with decision makers and civil society stakeholders, and deliver support for research. Only then can the global community move towards building truly resilient health systems that are socially just and that address climate change.We declare no competing interests.