While the introduction of command and control measures, as well as planning instruments, have experienced a quite long history, an increasing attention has been more recently given to the use of economic incentives/disincentives, aiming at encouraging, through price mechanisms, people decisions which will be more favorable for the environment. This attention is mainly due to the fact that market regulation is considered more effective, flexible and efficient: it does not, in fact, impose uniform behaviors to economic agents, while inducing more important changes for those they can result less costly.
This apparent superiority is strictly connected to the opportunity - both from a technical and political point of view - of implementing them, and above all to the ability of overcoming various barriers which can prevent their utilization and acceptability.
A wide collection of experiences from different States concerning the use of environmental taxes and charges and a scientific assessment of the environmental, economic and social impact of their introduction can be an important tool to face those barriers, which can be to an extent problems of fear of the unknown.