This story illustrates the importance of transdisciplinary co-exploration. Decision-support methods and participatory exercises can facilitate the co-exploration of ‘burning issues’, decision-making processes and climate information needs. Decision-making can be complex and influenced by a range of stressors, including climate variability and change. Although climate impacts are felt, climate information is not currently incorporated into the decisions and actions of many city planners and policymakers – very few use the appropriate type, scale and format of climate information, and future climate projections are rarely consulted. Hence, scientists and researchers can overestimate planners and policymakers’ grasp of climate science, and underestimate the complexities of city decision-making. Using a range of decision support methods and activities, co-exploration in FRACTAL cities has built shared understanding and trusted relationships, informed city agendas and strengthened confidence and capacities of researchers and decision makers.