This chapter aims to test a theory of "hegemonic stability," which posits that changes in the relative power resources available to major states will explain changes in international regimes. It seeks to account for changes in international regimes over time. The concept of international regime can be relatively narrow and precise or quite elastic. Regimes in the narrow sense are defined by explicit rules, usually agreed to by governments at international conferences and often associated with formal international organizations. The dependent variable in this analysis is international regime change between 1967 and 1977 in three issue areas: international monetary relations, trade in manufactured goods, and the production and sale of petroleum. The transformation in oil politics between 1967 and 1977 resulted from a change in the hegemonic coalition making the rules and supporting the regime: Organization of Petroleum Exporting Countries countries, particularly Saudi Arabia, replaced the Western powers, led by the United States.