One of the most striking tax developments in recent years, and one that continues to attract considerable attention, is the adoption by several countries of a form of "flat tax." Discussion of these quite radical reforms has been marked, however, more by assertion and rhetoric than by analysis...

Has the VAT proved, as its proponents claim, an especially effective form of taxation? To address this, this paper first shows that a tax innovation-such as the introduction of a VAT- reduces the marginal cost of public funds if and only if it also leads an optimizing government to increase the...