The convergence criteria group together those macro variables whose dimensions mean to put in good use, to potentiate and to strengthen the major benefits of integration, as their configuration, either before and especially after the adhesion in EU, represents strict and compulsory requirements for each state. The very reason stands in the strategic target of adopting euro currency, as an advanced phase of the integration which thus brings together the negative integration – meaning the abolition of the various obstacles in common market functioning -, with the positive integration – that means that minimum action of the public authority mainly aimed to ensure the coordination and harmonization of the economic policies.