Strategic delegation in the formation of modest international environmental agreements

We reassess the well-known “narrow-but-deep” versus “broad-but-shallow” trade-off in international environmental agreements (IEAs), taking into account principal–agent relationship induced by hierarchical structure of policy. To this end, we expand modest coalition formation game, which countries first decide on whether to join an agreement and then emissions a strategic delegation stage. In weak principals IEA, delegate domestic emission choices agent. Finally, agents all emissions. not joining choose maximize their own payoff, while IEA set internalize some exogenously given fraction ? externalities that cause members IEA. strong agents, who membership find crowds out efforts increase sizes less ambitious game first-best from principals’ point view can be achieved.