The United Nations Environment Programme's year book for 2012 shows that we are facing a number of environmental challenges, although scientists and policy makers have made headway on addressing some of the most pressing issues through new discoveries and investments. The year book presents the most important events and developments from the year, gives a picture of the status of key environmental indicators and highlights two emerging issues in detail: the benefits of soil carbon and the decommissioning of nuclear power plants. The publication is intended to strengthen the science-policy interface by informing interested parties about the most relevant environmental issues.