Throughout Europe, science and technology policy within the environmental field is currently in a process of transformation, which has been characterised by many observers as ecological modernisation. Emphasis is being given to preventive principles and so-called cleaner technologies in the quest for a more sustainable development. Each European country has, however, adapted the new doctrines and practices in distinctive ways. The main aim of the paper is to show how contemporary policies have been shaped by history, more specifically, by institutional (...) and cognitive traditions, and by national policy styles. By comparing 'ecological modernisation ' in Sweden and Denmark, we attempt to indicate how such national cultural differences affect the ways in which science and technology policies in the environmental field are formulated and implemented. (shrink)