The need for ecological sustainability has been translated into different indicators such as the ‘ecological footprint’ and the ‘planetary boundaries’. Analysis of both concepts concludes that the planet is currently undergoing a period of ecological unsustainability. For this reason, ecologists argue that various limits are required in order to move to a path of sustainability. The implementation of such limits has mostly been analysed from the perspectives of environmental rights and environmental justice, however research in terms of freedom is (surprisingly) (...) still lacking. In what way do such limits have an impact on freedom? I will argue that there are two different ways to analyse the relation between freedom and ecological limits: on the one hand, freedom is often referred to as being in competition with ecological sustainability and the limits it is required to impose, and, on the other hand, the impact on an individual’s freedom due to ecological catastrophe if strict limits are not implemented. Accepting that freedom is an important topic regarding ecological challenges, I ask which conception of freedom is better suited to answer this challenge as well as the required implementation of ecological limits. I compare and confront the closely linked conceptions of freedom as non-frustration and the closely linked conception of non-limitation, as well as non-interference and the conception of freedom as non-domination. After presenting these conceptions I examine their relationship with ecological limits. The conclusion is that the conception of freedom as non-domination is better placed to justify ecological limits necessary to promote an ecologically sustainable future. (shrink)