Title: The negative rebound effect of high-cost water and energy mitigation on climate change concern by Celine Nauges and Sarah Wheeler Climate change will require commitment by all levels of the community, but there is still uncertainty surrounding the best way to influence individual mitigation behaviour. This study analyses household survey data on water and energy climate change mitigation behaviour from eleven OECD countries in 2011, and provides new evidence of a form of maladaptation, namely a complex rebound relationship between climate change attitudes and mitigation behaviour. First, results confirm other studies that climate change concerns and economic incentives (in terms of electricity and water charges) positively influence mitigation behaviour. Second, we find that the more costly, in terms of time and/or money, are the mitigation actions of a household, the more likely undertaking such actions directly lessens respondents’ climate change concerns. This negative rebound effect is more likely to occur in ‘environmentally-motivated’ households, who are more likely to have stated they believe human actions can help mitigate climate change. Conversely, economic incentives in driving energy and water pro-environmental behaviour work better in non-environmentally motivated households. This highlights that a portfolio of policies is needed to drive mitigation behaviour.