How many international agreements should there be, and who should sign them? When policy issues are separable, linking them in a �grand international agreement� facilitates policy cooperation by reallocating slack enforcement power. When policy issues are substitutes, issue linkage further facilitates policy cooperation by increasing the amount of available enforcement power. The contrary happens when issues are complements. Then a better strategy can be to delegate policy issues to diferent independent national agencies. Constitutional rules that permit credible delegation to agents with dfferent objectives from governments facilitate international cooperation by generating stronger credible threats. Implications for multilateral agreements are discussed.