The article discusses how the law of personal jurisdiction has evolved since the landmark case of International Shoe v. Washington. Chief Justice Stone's opinion in this case played a significant role in changing the rules that previously limited personal jurisdiction. The law has shifted towards more flexible and case-by-case approaches, with fewer strict rules in place. This shift was influenced by Legal Realism, a legal theory that focuses on practical outcomes rather than rigid rules. The article highlights the strong connection between Chief Justice Stone and Legal Realism advocate Walter Wheeler Cook, showing how their collaboration shaped the modern understanding of jurisdiction and choice of law.