Book excerpt: The U.S.-Mexico border is the busiest in the world, the longest and most dramatic meeting point of a rich and poor country, and the site of intense confrontation between law enforcement and law evasion. Border control has changed in recent years from a low-maintenance and politically marginal activity to an intensive campaign focusing on drugs and migrant labor. Yet the unprecedented buildup of border policing has taken place in an era otherwise defined by the opening of the border, most notably through NAFTA. This contrast creates a borderless economy with a barricaded border. In the updated and expanded second edition of his essential book on policing the U.S.-Mexico border, Peter Andreas places the continued sharp escalation of border policing in the context of a transformed post-September 11 security environment. As Andreas demonstrates, in some ways it is still the same old border game but more difficult to manage, with more players, played out on a bigger stage, and with higher stakes and collateral damage.