To launder money is to hide its illegal origin. The fight against money laundering is supposed to disrupt laundering in its various forms – especially what is done by third party launderers and leaders of criminal organizations – and in the process, to undermine the financing of and profiting from crimes ranging from drug trafficking to terrorism. This fight delivers less than what it promises. Like many other enforcement systems, the fight against money laundering involves three major components: statutes with criminal penalties charged by prosecutors, rules administered by regulators, and detection systems primarily run by investigators. A close analysis of its three components reveals the fight to have quite a limited scope, involving (1) the disproportionate imposition of severe penalties on predicate offenders who are easily detected; (2) lax and narrowly-focused regulatory authority; (3) limited capacity to detect a range of chargeable domestic and international offenses; and (4) global diffusion of a fight against money laundering that leaves implementing authorities plenty of room for discretion and lax enforcement. These limitations probably arise not because of blindness or bad intentions but because the major players involved in running the system – including legislators, prosecutors, investigators, and regulators – face a tangle of incentives that leads them to dilute the intensity and scope of enforcement against some targets and to enhance the sanctions faced by other targets. This is hard to defend. The legislature has already set punishments for underlying criminal offenses, which are distorted by the frequent use of money laundering charges against predicate offenders. At the same time, while there is some evidence that suspicious activity reporting probably helps identify drug money placement in banks, the system can do little to detect and disrupt the larger universe of criminal financial activity that is so often vilified by pro-money laundering enforcement rhetoric. Some changes in the system enhancing audit trails and strengthening suspicious activity reporting (using information technology) could be defended in the name of making the system work, though politics would make them difficult to achieve. In the meantime, any inequities in the detection of predicate crimes end up being reproduced in money laundering prosecutions, and the system’s most compelling objectives – detecting crimes in a new way, and targeting third-party launderers and leaders of criminal networks – seem mostly beside the point.