The North American Free Trade Agreement (Nafta) has always been controversial. However, Nafta continues to be a political hockey puck, with the latest debate coming in the US presidential race. The regional agreement among the governments of Canada, the United Mexican States and the USA that went into force on Jan 1, 1994, was intended to implement a free trade area among the three countries and to set up infrastructure to manage it. The main purpose from a US perspective was to provide cheaper labor and opportunities for American investors, especially in the finance sector. Once implemented, it opened up access to cheaper labor, and, for many industries and sectors, it opened up the markets in a way that had not been seen before. Nafta also became a model for trade agreements between a developed and developing country. The US and Canada have each used this model in subsequent trade agreements with developing countries.