Twenty-five years ago, Princeton economist David Bradford designed what he called the X Tax. The idea--a progressive consumption tax--generated lots of discussion among tax experts. Wonks loved it for its elegant simplicity though there were (and are) real questions about how the tax would work in an increasingly international economy and how it would treat financial services. David’s idea never got much attention beyond the world of tax geeks.  But Bob Carroll and Alan Viard, in their new book Progressive Consumption Taxation: The X Tax Revisited (AEI Press 2012), are attempting to bring new attention to the design. Bradford, who was a senior Treasury official in the Ford Administration and a top economic advisor to President George H.W. Bush , died in 2005. The X Tax is a consumption tax, essentially a European-style value added tax with a couple of key innovations.  Most important, unlike many consumption taxes, it is progressive. In effect, the X Tax divides consumption into two pieces—wages and business cash flow. Households are taxed on wages, but unlike a VAT, they pay at progressive rates rather than a single flat rate. Businesses pay one rate on their gross receipts, but get to deduct wages. The top individual rate is equal to the business rate. Because it is fundamentally progressive, the X Tax addresses the most common criticism of consumption taxes—that they impose a greater burden on low-income households. This happens because people with lower incomes consume more of their money than the rich. There are other ways to solve this problem. The VAT proposed by Mike Graetz, for instance, would give couples a tax exemption of $100,000 (and provide a rebate for those who owe no tax). Graetz, however, still retains both the individual and business income tax while the X Tax completely replaces the existing system.     Economists will argue over which model makes more sense. But both are worth serious consideration when/if Congress really debates tax reform. Graetz can, and frequently does, speak for himself (with, among other things, great humor). Carroll and Viard deserve a lot of credit for being new voices for Bradford’s old idea.   It is, btw, fascinating that so much of the debate over consumption taxes is among conservatives. These taxes are in extremely bad odor among most Republican politicians these days. Yet, House Budget Committee Chairman Paul Ryan (R-WI) and former GOP presidential hopeful Herman Cain (who could ever forget 9-9-9) both supported versions of such a levy. Bradford, of course, was an aide to GOP presidents. Graetz was a top Treasury official for the first President Bush. And Carroll and Viard are both known as conservative tax scholars.     Bradford understood how controversial consumption taxes can be—that’s why he called his idea an X Tax. But whatever you want to label it, his design is worth consideration. There few new ideas in tax policy, so it never hurts to revisit one of the old ones. Thanks to Bob Carroll and Alan Viard for doing so.