The book "Financial Cryptography and Data Security" is a comprehensive collection of research findings that emerged from the contributions of the 18th International Conference on this topic. The conference took place in March 2014 in Christ Church, Barbados, and attracted numerous experts in the field of financial cryptography and data security. This volume includes 19 revised full texts and 12 short contributions, selected from a wide range of submissions. The topics covered are diverse, ranging from payment systems to cloud and virtualization technologies, as well as elliptic curve cryptography and privacy-friendly systems. The contributions provide valuable insights into current challenges and developments in financial cryptography and its application in the modern digital world.