This talk was delivered by Simon Mackenzie at the conference on ‘Prevention and fight against illicit trafficking in cultural property, the national and international dimension‘ organised by the International Scientific and Advisory Council of the UN Crime Prevention and Criminal Justice Programme, at the Università Cattolica del Sacro Cuore in Milan on 16 January 2013. The presentation was written and put together with Jessica Dietzler. The text of the empirical overview part of the talk is based on a chapter originally written by Neil Brodie and published as Brodie, N. (2012) ‘Uncovering the antiquities market‘, in R. Skeates, C. McDavid and J. Carman (eds), The Oxford Handbook of Public Archaeology, Oxford: Oxford University Press, 230-252. A final written version of the updated empirical review part of the paper will be published in autumn 2013, in the edited collection of the conference papers which is scheduled to appear as “Prevenzione e contrasto dei reati contro il patrimonio culturale. La dimensione nazionale ed internazionale” published by Vita e Pensiero. The review of criminological theory is currently being developed and extended for separate publication.