American divorce law was transformed by the Supreme Court in a series of decisions beginning with Williams v. North Carolina in 1942. These constitutional full faith and credit cases resolved a long-standing federalism problem by redefining the scope of state power over marital status. With these decisions, the Court shifted from an analysis based on the competing interests of different states to an approach that highlighted the individual interests of the parties involved. This change fundamentally altered state power over the family by extending to individuals greater control of their marital status. In the process, the Court cleared a path for innovations including unilateral no-fault divorce and divorce based on mutual consent and laid the foundation for a stronger national role in domestic relations law.