The essay analyses the costs and benefits of federalism, showing that many of them are typical of decentralization and therefore present in all the modern unitary states with decentralized bodies. Federalism has costs and benefits as regards property rights in relation to the exercices of constitutional powers. The benefits of federalism derive from vertical competition among the various levels of power. The federal state is superior to the confederal or unitary state because it guarantees that competition will continue even if one or more competitors are defeated, since it is not possible to regain powers arbitrarily and unilaterally. The need to regulate and consolidate rights generates the costs specific to federalism. The superiority of the federal state does not imply that in the future all states will adopt constitutions of a federal nature because the type of government system produced depends on particular historical circumstances and random events.