The numerous environmental flow assessment methods developed over the last several decades typically assume a stationary climate. The 2018 Brisbane Declaration recognizes the importance of climate change for environmental flows. Beyond this, however, we contend that to effectively manage environmental flows under changing climates, we need to fundamentally re-think the structure of environmental flow assessments. We present a new approach that moves away from a static set of flow recommendations, providing managers with tools to make trade-off decisions regarding ecological outcomes under future uncertainty. Key elements of our approach are that it i) is embedded within a participatory adaptive management framework that addresses the dynamic nature of social-ecological systems in changing climates; ii) fosters meaningful community stakeholder engagement to support ongoing adaptive management; iii) uses mechanistic flow-response models to improve the prediction of likely responses under unknown futures; iv) makes predictions of environmental flow performance across many climate futures; and v) links to monitoring and research programs to fill present and future knowledge gaps. In the Kaiela (lower Goulburn) River, Victoria, Australia, we recently completed an environmental flows assessment using this approach. We will provide a brief overview of the project and contrast it to what a ‘standard’ environmental flow assessment in Victoria would have looked like. As we move into a future where the only certainty is that the climate will be different to today, such approaches will be vital to ensure that the major investment of taxpayer funds in environmental water is used to its best effect.