Tributi ambientali, accertamento, Unioni di Comuni - The article points out the difficulties Regions will have to face in exerting real taxing autonomy because of the scanty possibility of implementation of taxraising practices that should not violate the principle of double taxation. Environment taxation, which might have some margins of operation, poses quite a lot of identification problems as far as the practice of legislation power is concerned. Art. 117 of the Italian Constitution does not attribute local authorities any possibility of direct exertion of legislative power, so that taxing autonomy is even more impaired. Thus the Author suggests that the raising of fiscal revenues should take place through the promotion of wider participation in the assessment of already existing tax arrangements by means of the creation of operative synergies via various forms of association, rather than by the imposition (in any case quite problematic) of new local taxes.