When nations divide, whether peacefully or through violence, there are many issues beyond politics to negotiate in the aftermath. Understanding the concerns that are likely to confront separated states is vital in establishing stability in new states. Examining case studies in Africa, Europe, and Asia, international security expert Gregory Treverton provides a detailed guide to recent national divisions that range from the partition of India to the secession of Eritrea from Ethiopia. Dividing Divided States offers an overview of the ways different states have handled such contentious issues as security and citizenship, oil and water resources, assets and liabilities, and the rights of pastoralist groups. In each case, Treverton considers how the root causes of secession—such as long-simmering conflicts, nationalist politics, and changed geopolitical circumstances—impact the effectiveness of policies that form new nations. Dividing Divided States serves as both a source of ideas for future secession policies and a reminder that, while the motivations and outcomes of secessions may differ widely, separating states face similar challenges in dividing populations, natural resources, and state resources. This book offers considered and cautionary lessons for policy makers and policy researchers alike.