North Korea possesses nuclear weapons. Iran is poised to acquire them in the next decade. How the United States and other nations seek to roll-back these burgeoning nuclear powers is among the most urgent issues of the day. Patrick Cronin and the contributors to this volume offer complementary international perspectives on these threats and the peaceful responses to grapple with the Iranian and North Korean nuclear programs and the wide ranging security concerns posed by these two nations. The four essays dedicated to Iran and the five essays focusing on North Korea contained in this work examine the many potential dangers posed by each respective country. The writers of the essays consider Iran and North Korea as the two most likely triggers for expanded interstate warfare and as such they should be the collective concern of the global community, not just the United States, Great Britain, or a small number of other countries.