Most economists agree that trade liberalization raises incomes and living standards. To achieve trade liberalization, though, countries must sometimes first reach trade agreements. And trade agreements, as William Gruben and John Welch observe, may intertwine elements of both liberalization and...

The controversy over the success or failure of NAFTA is now bleeding over into discussion about the benefits of extending the trade accord to other countries in the Western Hemisphere. The NAFTA debate has typically focused on its impact on employment. But to understand the overall economic...