Human trafficking is now widely recognised as a complex issue, which requires
differentiated measures or ‘holistic’ approaches as the literature names them. More
effective anti-trafficking measures are connected with the limitations or lack of
knowledge about human trafficking. ‘Lack of knowledge’ about the phenomenon is
often identified as one of the main constraints on more effective governance. ‘The
need for better data’ is now unanimously recognised by experts as one of the
necessary steps for improving anti-trafficking strategies (Laczko 2002, 2007). It is
now widely acknowledged that the data on human trafficking is insufficient,
unreliable, incomparable and limited (Ogrodnik 2010). The UNODC Executive
Director Antonio Maria Costa deems it a ‘knowledge crisis’ and goes on to explain its
ramifications for anti-trafficking: