The principle of reciprocity is basic to the acceptance of the compulsory jurisdiction of the Court. According to this principle, the Court's jurisdiction exists only to the extent that both countries that are parties to a dispute have accepted the same obligations regarding the use of the Court to resolve that type of dispute. The Court has consistently interpreted the condition of reciprocity contained in the Optional Clause of the governing statute as reciprocity as applying to the scope and substance of disputes and not to the formal conditions of the creation, duration, or extinction of individual nations' declarations supporting the Optional Clause. Thus, in the recent case of Nicaragua v. United States, the Court required the United States to abide by the clause in its 1946 declaration providing for 6 months' notification of its termination of the declaration. In contrast, the United States contended that that it should have been allowed to immediately modify its declaration, based on the principle of reciprocity with Nicaragua. Countries concerned about the potential for inequity should amend their own declarations, because extending the application of reciprocity would undermine the effectiveness of the Court's compulsory jurisdiction. 105 footnotes.