Recently, a number of specialty areas have developed dealing with the economics of natural systems, resources and the environment. These include natural resource economics, environmental economics, ecological economics and bioeconomics. As well, new government departments, research institutes and tertiary courses have evolved in these areas. This paper examines the evolution and characteristics of the new areas of specialisation, and their relationship with the more traditional discipline of agricultural economics. Environmental economics is viewed as a wider interdisciplinary field than natural resource economics, and ecological economics or bioeconomics is depicted as a branch of natural resource economics dealing with living resources.