One countermeasure against organized crime is to provide effective protection for witnesses who have been involved in and have inside knowledge of organized crime personnel and networks. A second countermeasure involves reversing the burden of proof for confiscating the proceeds of crime, such that the offender must prove that a particular asset has not been acquired through crime proceeds. A third countermeasure is the interception of communications along with intrusive surveillance, in order to gain incriminating information. A fourth recommended countermeasure is crime analysis, which involves the collection and analysis of data on organized crime's operations, so as to tailor investigative techniques and prevention measures to the criminal methods being used by organized crime. Cross-border cooperation is another best practice that improves the effectiveness of investigations of transnational organized crime. The identification and development of profiles and movements of key members of criminal organizations is also an effective means of enhancing investigations and impeding the activities of organized crime. In the case of human trafficking perpetrated by criminal groups, it is helpful to use victims as witnesses to identify trafficking methods and the traffickers. Finally, there should be legal administrative measures designed to prevent organized crime from infiltrating and developing legitimate businesses by using capital from criminal enterprises. Similar measure should be used to counter organized crime's corruption of public officials. Each field survey involved three European countries that were selected according to previous information about their experience in dealing with one of the eight survey topics on organized crime countermeasures.