Abstract: Today's headlines are filled with stories about threats to cultural heritage worldwide from erosion and neglect to pillage and outright destruction. Damage to archaeological sites through illegal excavations is particularly acute, since archaeological context is irreversibly destroyed by the search for objects to fuel an antiquities black market. This lecture explores three decades of work by the U.S. Government to address this problem through the lens of cultural property agreements. These international treaties, a function of U.S. law that implements the UNESCO Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property, help staunch the pillage of archaeological sites in countries like Italy, Cyprus, and Egypt (pending), and curb the trafficking of objects through the enforcement of U.S. import restrictions. Agreements also provide a framework by which our countries--through governments, universities, museums, and NGOs--collaborate on activities of mutual interest including excavations, exhibition and research loans, and preservation of archaeological and historical sites.