Financial crimes are increasingly growing in sophistication. Criminals accumulate significant sums through offences including drug trafficking, fraud, extortion, corruption and tax evasion. Different government agencies may be involved in detecting, investigating and prosecuting these offences and recovering the proceeds of crime. This second edition of Effective Inter-Agency Co-operation in Fighting Tax Crimes and Other Financial Crimes describes the current position in 48 countries with respect to the law and practice of domestic inter-agency co-operation in fighting tax crimes and other financial crimes. It outlines the roles of agencies in different countries, legal gateways to enable these agencies to share information and other models for co-operation, such as joint investigations and the establishment of intelligence centres including officials from different authorities. The report identifies a number of successful practices based on countries’ experiences and makes recommendations for how inter-agency co-operation may be improved.