In the way of giving the extradition there must be fulfilled a series of background and formal conditions. When we refer to background conditions, we talk about persons and the crimes submitted to extradition. The formal conditions report those aspects which are connected to the phases of the extradition procedure that consists of the legitimacy ascertainment and of the regularity of the extradition application, the procedure ahead of inquiry devices and juridical instance. Among the formal conditions there are the rules that are talking about the preferences of the states succession ahead of extradition.