An interstate compact is a formal agreement between two or more states in the United States. These agreements are used to address shared concerns, such as resource management, transportation, or environmental issues. Interstate compacts require approval from the U.S. Congress to ensure they do not conflict with federal laws. These compacts help states collaborate effectively and can lead to better solutions for regional problems. For example, the Port Authority of New York and New Jersey is an interstate compact that manages transportation and infrastructure in the New York metropolitan area, demonstrating how states can work together for mutual benefit.