Prostitution: A changing situated market of estranged commodified sex

It is estimated that globally 40-42 million people are involved in prostitution (Fondation Scelles, 2012), and that 70% of the women engaged in prostitution in Western Countries are migrants.
As involved criminal groups earn around 3 billion USD a year, prostitution is assumed to be one of the most lucrative illegal businesses in Europe (UNOCD, 2010). Thus there are many global economic interests in the field, and authorities wish to intervene. The question is how?

In Denmark the discussion is ongoing as well as parallel to an international debate, and questions are raised in international organisations such as the UN and the EU.
On the one hand it is argued that a general decriminalisation of all practices concerning prostitution should be legalised and normalised, including procuring. Lately, Amnesty International advocated full decriminalisation/legalisation of all aspects of prostitution, including procuring.
On the other hand, this has been publically criticised by organisations like Equality Now, anti-trafficking organisations and networks of researchers from over 30 countries including Denmark, where the criminalisation of costumers has also been advocated.