Independence referendums represent a contemporary approach to territorial secession, rooted in the Enlightenment and the 1848 national revolutions. This chapter identifies four distinct historical waves of independence referendums. The first period began in 1791 and was followed by several votes in British and Spanish colonies of America and a series of referendums held after the collapse of the Austro-Hungarian Empire. The second wave of independence referendums started in the wake of decolonisation in Africa, the Caribbean, and Asia. Independence referendums returned to the international agenda after the break-up of the Soviet Union in 1989 in Central and Eastern Europe and Central Asia. Since then, independence referendums have been conducted to address conflicts in diverse contexts. This instrument is now considered the primary tool for resolving territorial conflicts between secessionism and unionism.