Nature-Based Solutions (NBS) have the potential to respond to climate change, enhance biodiversity and improve environmental quality while contributing to economic regeneration and social well-being. Yet there is a substantial gap between the promise of NBS and their uptake. To unlock the potential of NBS for sustainable urban development, NATURVATION will take a transdisciplinary, internationally comparative approach to: advance assessment approaches (Objective 1) to capture the multiple impacts & values of NBS to deliver a robust evidence base for decision-making; enable innovation (Objective 2) to identify the most promising governance, business/finance and participation models and how to overcome the systemic conditions that currently limit their use to support systemic integration; and generate momentum to realise the potential of NBS through co-design, co-development & co-implementation of new partnerships, knowledge, recommendations, processes and tools required to build capacity, enable replication and foster cultural change (Objective 3). Our transdisciplinary approach working with ‘urban-regional innovation partnerships’ in six different cities and a Task Force of highly respected international organisations working in this arena integrates science, social science and humanities (SSH) and practical expertise and experience to achieve a step-change in the use of NBS for urban sustainability.