AbstractEuropean environmental policy-making is particularly complex because it must respond to internal political and economic agendas, the differing environmental conditions of member countries, world politics and expert assessments of environmental dantage. Experts have many functions in this process, ten of which are outlined, ranging from providing ‘greenwash’ and an excuse for doing nothing, to problem solving and arbitrating in disputes. By ignoring many of these functions, the role of expertise in public policy debates tends to be underestimated in relation to politics, but overestimated in its impact on policy. Making sure that openness and representativeness prevail in national political processes would best serve European societies in protecting their environments.