The paper defines basic concepts such as money laundering. It also analyzes the principles and fundamentals of international regulations, and the regulatory system in Croatia related to money laundering prevention. The paper presents a description of the organization and remit of the Money Laundering Prevention Office. The paper highlights the forms of money laundering of natural persons and it states why international cooperation is important to prevent the money laundering. The infiltration of dirty money is a crucial problem for national economies. The purchase of shares, real estate, the establishment of dirty investment funds and the use of the banking system to embed such resources is a danger, not only to the credibility of a whole country, but also to the security of the financial and banking system. Croatia has adopted statutory measures aimed at the prevention of suspicious financial transactions, namely the prevention of money laundering. Launderers constantly find new ways to make use of new non-financial channels in order to expand their activities to real estate, artworks and insurance. Therefore, it is necessary to keep up with European approaches and recommendations and to strive for improvement of the laws to modernise the system with the adoption of new regulations harmonised with international standards.