Several of the preceding contributions to this special issue have raised critical comments and questions on the concept and research agenda of ecological modernization. It is our impression that these comments not only reflect academic ingenuity, but also a broader and growing hesitation about the concept and its usefulness, as similar scepticism was also expressed by participants at the international workshop on ecological modernization in Helsinki. As the term ecological modernization has grown popular among leading politicians and policy-makers, so has the dilution of it. In this paper, we make an attempt to move away from the purely heuristic use of ecological modernization, by clarifying both its origins and meanings. For connoisseurs of the concept, our paper may be seen as a recapitulation, rather than as an innovation; our mission is not to reinvent a concept, but to clarify its origins and connected dilemmas. In essence, ecological modernization refers to a specific type of foresighted and preventive environmental policy, which is closely related to the precautionary principle and, therefore, involves long-term structural change of the patterns of production and consumption. The agenda for ecological modernization, and for an associated ecological tax reform, was promoted by scientists outside of the economics profession, but helped breathe new life into the dormant discipline of environmental economics. In recent years, much of the debate on the opportunities of ecological modernization have been 'captured' by economists, who tend to perceive it in the vein of conventional efficiency measures. In view of the serious environmental problems facing the global community in the 21st century, ecological modernization as a concept, in our opinion, only makes sense if reserved for a reference to more radical structural changes that promote ecological consistency rather than ordinary efficiency. Copyright