[fre] Acquisition d'information, innovations et irréversibilités. . Cet article étudie des stratégies de protection des lacs américains menacés par les pluies acides. L'Agence de protection de l'environnement, responsable du programme de protection, est confrontée à des incertitudes...

[eng] In this paper which deals with global environmental problems, we use an evo­lutionary approach in order to determine the conditions under which O.E.C.D countries are led to reduce unilaterally their pollution emissions. Thus we remark that a country's choice of a unilateral reduction...

[eng] Provocated unilateral commitment in the presence of global environmental change. . In this paper which deals with international pollution, we attempt to explain why some countries other than those who are members of the O.E.C.D accept to reduce unilaterally their pollution emissions. This...