Money laundering causes significant societal harm through its connection to predicate crimes. Efforts to address money laundering must be coordinated at the international level because the global financial system allows individuals to easily move funds across borders. Despite the importance of this topic for international relations, the dynamics of how, why, and when states cooperate to address money laundering remain poorly understood. This dissertation presents three studies that begin to shed light on these questions. Using the synthetic control method, we test whether states experience economic harm following news of a major money laundering investigation. To enable this research, we collected a first-of-its-kind dataset of money laundering investigations based on news coverage in two major international newspapers, which provides insight into which countries carry out investigations and where investigated entities are located. We also test whether states experience economic losses after being placed on the “blacklist” of an international organization, the Financial Action Task Force (FATF), using the synthetic control method. Our results support the conclusion that although states experienced economic harm following blacklisting by the FATF, there is no clear evidence of reputational harm (measured by economic losses) following news of a major money laundering investigation. We also measure how well countries enforce a new anti-money laundering law for cryptocurrency by collecting transactions directly from cryptocurrency exchanges, which allows customers to trade cryptocurrency for government-issued currency. Use bunching estimation and instrumental variable estimation, we show that countries vary in how stringently they enforce the new law; this finding suggests that current evaluation methods (including at the international level) do not adequately measure how well countries enforce these laws, hindering international efforts to obtain a high level of efficacy across countries. Our results call for the continued empirical study of international-level efforts to combat money laundering.