A collapsed North Korea would pose a momentous test to the future of the region. The five regional powers—South Korea, China, Japan, Russia, and the United States—are ill-prepared for such an event, partly because of the act of planning for it would upset North Korea. However, the potential challenges of a collapse are too great to ignore. This study presents an historical and political analysis of the increasing risk that North Korea may collapse. A comparison with earlier cases suggests that triggers and indicators of collapse can be identified, including increasing cross-border information flows, defections, and the possible death or incapacitation of North Korea’s leader. Further, the large and growing economic disparity between North Korea and its neighbors, South Korea and China, points to likely consequences of collapse, including possible mass migration. The study then examines the roles of South Korea, China, the U.S., Japan, and Russia in the future of the Korean peninsula; it concludes with a further consideration of the paradox of collapse planning, but argues that it would be better to run the risks entailed in the exercise than to be caught flatfooted when a collapse occurs. The analysis is based on interviews, surveys, and documents in English and Korean. / text