Municipal solid waste is often transferred to landfills in other regions or states. While municipalities frequently resist imports, the interpretations of the Interstate Commerce Clause require that landfills accept waste regardless of its origin. This may require importers to act in ways that are not in their own best interest. The analysis of this paper suggests that importers benefit from trade when their landfill is so large that it is not exhausted at the end of the planning period. However, when landfill capacity is sufficiently scarce, importing waste is not welfare enhancing. Such municipalities have considerable motivation to try to de facto exclude waste from outside the municipality.