Leaders from Colombia, Chile, Peru and Mexico gathered in the Chilean Atacama Desert this week to sign an agreement pledging unity under the newly minted Pacific Alliance. First envisioned a year ago during a meeting in Lima, the alliance's first move will be to remove all bilateral visa restrictions, and the countries hope that the bloc will evolve into a multilateral free trade area. The Pacific Alliance unites four of Latin America's most trade- and business-friendly countries. According to Chilean President Sebastian Pinera, the bloc intends to focus explicitly on developing a trade agenda with Asia. The agreement is also sure to impact trade with the United States, a major export destination for all three countries. Perhaps the most striking aspect of the agreement is the way it contrasts with Latin America's other major trade grouping: Mercosur, or the Market of the South.