Woods (2006) and Daley, Mullin, and Rubado (2014) examine the implementation decisions of state governments under national laws. Schlager, Heikkila, and Case (2012) examine how states can coordinate activities to manage interstate resources outside of federal policy control. The authors study interstate river compacts, which are constitutionally sanctioned agreements between two or more states to allocate and manage rivers that flow across state boundaries. Specifically, they examine the compliance costs associated with the resolution of disputes over interstate river compacts, finding that costs tend to be equally shared among states when disputes are settled in voluntary conflict resolution venues as opposed to compulsory venues. Moreover, their study shows that how states administer compacts also shapes the pattern of compliance costs. In states with centralized structures, the costs are borne by state water agencies directly, whereas in states with polycentric structures, costs are generally shared between governments and water users. Schlager, Heikkila, and Case’s findings offer important lessons for understanding how states implement their obligations under interstate river compacts, as well as potentially compliance with other types of interstate agreements.