Regional Integration and the Co-ordination of Capital Income Taxation

type="main" xml:lang="en"> This paper addresses the question of the need for income tax harmonization in the context of regional integration. It analyses the international distortions and fiscal interdependence arising in the presence of tax rate differentials both under a theoretical and an empirical perspective, and with reference to actual experiences of harmonization attempts. Attention is also paid to the influence of the countries’ size on the results, to the strategic behaviour of countries under different international taxations rules, and to the relationships with the countries excluded by the integration process. International tax uniformity does not appear to be the preferable solution, even if some form of concerted agreements might help in reducing inefficiencies deriving from taxation differentials. For instance, in the case of highly mobile factors, like financial capital, if the integrating countries apply the source principle and the interest rate is the same across them, the source-based tax rate on non residents must equal the residence country tax rate on residents. Such a rule would allow the countries to set autonomously their tax rate and, at the same time, eliminate cross-border effects. If there are more than two integrating countries, the tax rates on non residents should discriminate according to the internal tax rate of the residence country. (J.E.L.: H87, F20, H20).