Free trade promotes global efficiency through specialization.  Operating at maximum productivity is one of the most important aspects of an efficient economy. The right resources and technology must be combined to produce the right amount of goods to be sold for the right price. Therefore all markets should strive for highest efficiency. In order to maximize efficiency in the international economy, countries need to utilize their comparative advantage. This means producing what you are best at making, compared to other countries. If Mary is the best carpenter and lawyer in the US, but makes more money being a lawyer, she should devote more of her time to law and pay someone for her carpentry needs. Mary has an absolute advantage in law and carpentry, but someone else has a comparative advantage in carpentry1. Comparatively it makes more sense for someone else to do the carpentry, and for Mary to be the lawyer. It is the same in the international economy. Countries can be more efficient and productive if they produce what they are best at based on their domestic resources and populations, and trade for other goods. This promotes efficiency and lower prices. Free trade enhances this. The Doha round that is currently being debated in the World Trade Organization would reduce trade barriers and promote free trade, economies of scale, and efficient production of goods. It is estimated that the Doha round would increase the global GDP by $150 billion alone just by promoting free trade2. Free trade leads to specialization and efficient production, which ultimately would increase the size of the global economy and the individual economies in it. 1 Library of Economics and Liberty, "Comparative Advantage",  2 Meltzer, Joshua (2011), "The Future of Trade", Foreign Policy Magazine,