Nowadays organized crime is a very important political issue in Europe. However, scientific studies on the nature and seriousness of this problem are very scarce in the member states of the Council of Europe and the European Union. This national study on organized crime in the Netherlands was prepared for the Commission of Inquiry of the Dutch Parliament that recently made an investigation into the regulation and use of undercover policing. It not only contains an analysis of the contemporary manifestations of traditional organized crime, but also answers the question whether organized crime already has penetrated legitimate sectors of the economy or not. In addition special attention is paid to the role of the liberal professions and the banking system; and to the use of counter-strategies by criminal groups (corruption, intimidation, violence, disinformation, etc.)