Chapman v. Goodnow's Administrator was a United States Supreme Court case that dealt with the issue of whether a state court could enforce a contract that was made in another state. The case involved a contract between a New York resident, Goodnow, and a Massachusetts resident, Chapman. Goodnow had agreed to pay Chapman a certain amount of money for the sale of a horse. After Goodnow died, his administrator refused to pay the money, and Chapman sued in a Massachusetts court. The administrator argued that the contract was invalid because it had been made in New York. The Supreme Court held that the contract was valid and enforceable in Massachusetts. The Court reasoned that the contract was valid under the Full Faith and Credit Clause of the United States Constitution, which requires states to give full faith and credit to the public acts, records, and judicial proceedings of other states. The Court also held that the contract was valid under the law of Massachusetts, which allowed contracts made in other states to be enforced in Massachusetts courts. The Court's decision in Chapman v. Goodnow's Administrator established that contracts made in one state can be enforced in another state, provided that the contract is valid under the law of both states. This decision has been cited in numerous subsequent cases involving the enforcement of contracts across state lines.

In Chapman v. Goodnow's Administrator, the Supreme Court was tasked with determining whether a state court could grant an injunction to prevent a party from bringing suit in another jurisdiction. The majority opinion held that such an injunction would be unconstitutional and violate the full faith and credit clause of the Constitution. However, Justice Field dissented on this point, arguing that states have broad authority to protect their citizens from vexatious litigation by enjoining suits brought in other jurisdictions. He argued that while it is true that states must give full faith and credit to judgments rendered by other courts, they are not required to extend this same courtesy when it comes to restraining parties from filing lawsuits elsewhere. Furthermore, he noted that if Congress had intended for all injunctions issued by one state court against litigants residing outside its borders were invalidated under federal law then there would be no need for any legislation related thereto as it would already be prohibited under existing constitutional provisions; thus implying Congress did not intend such a result when enacting laws regarding interstate injunctions