This chapter opens Part IV on ecological-economic modelling. It starts with a brief synopsis of the history of economic thought that leads on to an outline of the subdisciplines of environmental economics and ecological economics. Major achievements highlighted include, among others, the development of market-based instruments to protect the environment, the consideration of the dynamic complexity of coupled ecological-economic systems, and the development of the concepts of resilience and sustainability. The chapter concludes with recommendations for ecological-economic modelling, which include the consideration of uncertainties, non-linearities, feed-back loops, evolution and adaptation and the use of adeqate models of human behaviour.