type="main" xml:id="ecca12074-abs-0001" <p>Experience from climate policy suggests that full cooperation among all countries is not a likely outcome. In this paper we therefore consider the case where only members of a subgroup of countries cooperate by reciprocally matching their public good...</p>

International environmental protection like the combat of global warming exhibits properties of public goods. In the international arena, no coercive authority exists that can enforce measures to overcome free-rider incentives. Therefore decentralized negotiations between individual regions...