This book focuses specifically on independence referendums held in liberal democracies. In theory, these two concepts are not incompatible since independence referendums represent a form of direct democracy that should be respected in democratic regimes. This was the principal message of the Badinter Commission during the Yugoslav crisis: a legitimate and democratic procedure of secession should lead to democratic stability and avoid violence. However, this relationship is more complex in practice, since an overwhelming majority of liberal democracies impose a series of territorial integrity clauses in their constitutions, such as the “eternity clause”, “inviolable values”, or a “duty of protection”, to avoid secessionist temptations. By contrast, very few countries include constitutional secession clauses regulating the separation of their own regions. As a result, independence referendums remain rare electoral events, not only because voters prefer stability but also because of the complexity of implementing them.