This article summarises briefly what is known internationally about how ‘organised crimes’ are financed and how this differs from the financing of licit businesses. It shows how illicit financing might and does operate, noting that a key issue is the social capital of offenders and their access to illicit finance which ironically, may be easier if controls make it harder to launder money. It then reviews international evidence on how proceeds of crime are laundered, concluding with an examination of the implications of these observations for the study of organised crime and the effects of anti-money laundering efforts. In money laundering cases internationally, the most commonly prosecuted cases are not complicated. This is not evidence that there are no complicated cases, since the proportion of crime proceeds and crime financing that have been subjected to serious investigation is modest. There is a core contradiction between general economic policy pushed hard multilaterally for liberalisation of financial flows and a crime control policy intent on hampering them. No-one could rationally think that AML controls in general or financial investigation in particular will ‘solve’ organised crime completely or eliminate high-level offending: for there even to be a chance to achieve that, there would need to be a step change in transparency and effective action against high-level corruption along all possible supply chains. However more action (not just legislation) on these could facilitate interventions against the more harmful individuals, networks and crime enablers. The less complex financial activities of local drug-dealing gangs can be intervened against, without needing international cooperation or familiarity with sophisticated money laundering typologies.