The Bank for International Settlements (BIS) and its partner central banks within the Eurosystem, De Nederlandsche Bank and the Deutsche Bundesbank, are collaborating on Project Atlas, a data platform that aims to explore the macroeconomic relevance of cryptoasset markets and decentralised finance (DeFi). This project combines on- and off-chain data to provide central banks with tailored statistics and insights. The proof of concept phase focuses on international flows of cryptoassets. The platform collects data from crypto exchanges and public blockchains to analyze cross-border capital flows. The data collected so far shows substantial cross-border flows that are economically significant and unevenly distributed across regions. The project has received positive feedback from experts, who see its potential in providing valuable insights for central banks. The BIS Innovation Hub aims to develop solutions that can be used by central banks, and Project Atlas is a starting point for analyzing existing data and understanding the macroeconomic implications of crypto markets.