When will U.S. courts bring U.S. law to bear on the activities of foreign actors outside the United States? Over the past few decades, the number of domestic court cases that have projected U.S. law beyond U.S. borders has grown dramatically. On a smaller scale, other nations have begun to follow the U.S. extraterritorial lead. No longer solely the realm of international law and international institutions, domestic law increasingly plays a prominent role in global governance. As a result, the once neglected area of extraterritorial jurisdiction has taken on increased importance to political scientists, international relations scholars, legal academics, and international lawyers.

Into this mix comes Tonya L. Putnam's terrific and very readable book, Courts without Borders: Law, Politics, and U.S. Extraterritoriality. It is a valuable addition to a growing body of interdisciplinary literature that explores different ways transnational law is made. Putnam examines the politics behind judicial extraterritoriality. Why, she queries, have U.S. courts generally declined to exercise extraterritorial jurisdiction over product liability claims and alleged patent violations, but they are willing to enforce domestic statutes extraterritorially to disrupt international trading cartels, counter transnational securities fraud, or protect U.S. trademarks?