The chapter discusses how the mechanism of provisional or interim measures of protection is interpreted and applied in the context of the four main regional systems—with more extensive references to the work of the Courts and Commissions in the Inter-American and African Human Rights systems. The analysis in the chapter explores whether and when interim and provisional measures are available, the authority for ordering them, the rules regulating their use, the reasons underlying their request, their legal validity and binding nature, the difficulties of implementing them and the question of their enforcement. The chapter also provides some examples, considering the use of those measures in situations of extreme urgency, such as pending executions and expulsions.