Sustainable development, climate adaptation and urban resilience are becoming increasingly important issues for municipal governments. However, councils cannot address these issues alone, and are often hindered by a lack of clarity around the potential costs and benefits of taking action. This article sets out how public bodies can use alternative, collaborative approaches to understand climate risks better and thereby support the business case for adaptation. It highlights how Newcastle City Council worked with other local stakeholders to develop a shared understanding of how a major storm could affect services and infrastructures across North East England. This helped the authority to identify the potential costs of an extreme weather event, and informed its decision to invest in infrastructure that will help to protect future generations from similar incidents.