Within social work discourse, 'the environment' seems inevitably to refer to the socio-cultural environment. Such a focus reflects the domain that social work has defined for itself through various codes of ethics, as well as the theory and practice focus of social workers. Over a long period of time doubt has gradually been dispelled about the effect that humankind has had on the environment, and it is now largely accepted that global warming has an anthropogenic basis. This paper examines the place of social work in a world that is trying to come to terms with various ecological disasters, not the least of which is climate change. Social work is cast as a profession that needs to become more aware of the ways in which society is embedded in the natural world and our physical environment as a whole. The issue of social sustainability is explored as a focus for the relevance of social work knowledge and practice in this time of environmental crisis.