This research investigates the lack of critical attention to the presence, absence and function of ‘ecotopian’, or ecologically-ideal, visions of the future within ecocriticism and within contemporary climate change discourse. Whereas recent years have seen a huge rise in the number of dystopian depictions of the future, in an age of climate breakdown, from the mid-century, the presence of ecotopian visions of the future have significantly diminished. In many ways, this is entirely understandable, as the multiple environmental crises facing the planet have significantly worsened between 1945 and the present. However, this research asks what the role and function of ecotopian visions of the future are, both in contemporary climate change writing, and in environmental writing from 1945. It also investigates how ecotopian visions of the future have changed from the mid-century to the present day, and why ecocriticism has not meaningfully engaged with ecotopia's role. In a linked public engagement study, the research also explores the potential function of ecotopian thinking and writing as an engagement tool, asking whether engaging with positive environmental futures can motivate the public, and researchers, towards sustainable behaviours. Crucially, this work will help to understand the role, function and history of ecotopian visions of the future, and assess what we might have lost through the disappearance of ecotopian ideas of our future in the 'Age of the Anthropocene'. It will also ask what we might gain from embracing ecotopian thinking and writing as an environmental engagement tool.