Social representations of the greenhouse effect For the third time since spring 2000, the Ademe (French Agency for Environment and Energy Management) has conducted a national opinion survey about social representations of the greenhouse effect. Results of these studies show that public knowledge about these phenomenon is still poor. Nevertheless, a large majority of the sample is already convinced that global warming is a reality and that the consequences of this event might be harmful. Moreover, the public at large is aware of the fact that technical progress will not solve the problem by itself and that a change of social behaviour will be necessary. Daniel Boy