The environment forms the basis of all global social and economic systems, and the substrate for all development activities. This paper reviews the current state of the global environment. Whilst debates about the limits to growth continue, several inter-related indicators suggest that limits do exist, and are being dangerously exceeded. While all of earth's inhabitants depend on the environment for survival, poor people often depend very directly on the natural resource base for their livelihoods. Areas of particular concern from a development perspective include climate change, water resource management, and agriculture. Marginalised groups - such as indigenous peoples and women - are often the first to experience the impacts of environmental degradation, yet lack the political influence to redress them. Failure to meet the environmental Millennium Development Goals looks inevitable, in turn putting the achievement and sustainability of the other MDGs in jeopardy.