drug trafficking, trafficking in human beings, child pornography, and other serious trans-national offences. Thirdly, important EU information systems and databases (Prüm, SIS-II, ECRIS) have been created, enabling law enforcement and judicial authorities to gain access to essential information on criminal phenomena and organisations. Pursuing a practice-orientated approach, this work provides comprehensive coverage of all these measures, as well as the applicable rules governing data quality, data protection and data security. It is especially intended for law enforcement and judicial authorities who need to develop the appropriate expertise for the practical application of the above-mentioned principles. It also offers a solid basis of practical training material for police training centres and judicial schools.