The research report examines the impact of the Ukraine war on illicit financial flows (IFFs) in South Eastern Europe. It highlights that IFFs, which include activities such as money laundering and corruption, have detrimental effects on economic development and undermine the rule of law. The report emphasizes that Russia has taken advantage of its integration into the Western financial system to exploit governance gaps and engage in illicit finance. The Balkan region, particularly Serbia, has become a crucial entry point for illegal activities due to travel bans imposed on Russians. The report also discusses the role of illicit finance in facilitating drug trafficking, human smuggling, and illicit trade. It warns about the risk of weapons flowing into Ukraine from the Western Balkans and potentially ending up in the hands of criminal groups or being sold on the black market. The report concludes by providing recommendations for improving border control, police, and anti-money laundering authorities to counter organized crime involved in cash smuggling and money laundering.