The central theme of the analysis developed in the study is the identification of some logical properties that are expected to characterize the “separation-of-decisions” paradigm of the fiscal decision process. The latter refers to an institutional framework where collective choices of tax-sharing arrangements are assumed to be made in advance with respect to public expenditure decisions. A model is developed where the effects of this time lag introduced between the two sets of decision--the vaccatio legis--are analyzed. Two broad sets of results are derived. The first refers to the non-asymptotic properties of the model, that is, the ones that are expected to hold when the vaccatio legis increases up to the limiting situation where equiprobability is attained. Two basic mechanisms which potentially operate when the vaccatio legis increases are identified. One, the Consensus Effect, tends to make separate individual most preferred choices with respect to tax structures more similar to each other. The other, the Aspirations-level Effect, reduces the expected utility associated with each individual's most-preferred choice. It is seen that these mechanisms, when they are simultaneously at work, reinforce the effect of each other in reducing the amount of resources devoted to strategic activities and therefore in saving negotiation costs. Situations are examined, however, where either one or both of the mechanisms may not operate or may even operate in the "wrong'' direction. The second set of propositions analyzed deals with asymptotic properties of the "separation-of-decisions" formulation. It is pointed out the basic isomorphism of the model, that is, the fact that, since in the equiprobability situation individuals possess essentially the same decision ingredients (similar probability prospects, unique utility evaluator, identical net income opportunities) their choices cannot but be the same. The importance of this proposition comes in an indirect way. It shows that possible violations of some non-asymptotic properties-, namely the consensus mechanism, can be at most a local phenomenon. In the "long-run," full consensus is inescapable. A second asymptotic property discussed refers to the trade-off between equity and efficiency that is expected to be reflected in tax schemes selected under such limiting circumstances. It is shown that if tax-prices are uniform over quantities, if no complementary redistributional measures are allowed and if risk aversion prevails then there is no presumption that constitutionally preferred tax arrangements will fulfill Samuelson's well-known efficiency conditions. The analysis suggests that, in general, such arrangements will reflect a compromise between two separate normative principles, one of which calls for the maximization of aggregate taxpayers surplus and the other of which promotes equalization of separate individual surpluses. / Ph. D.