The 11th International Conference on Financial Cryptography and Data Security (FC 2007, http: //fc07. ifca. ai), organized by the International Financial Crypt- raphy Association (IFCA, http: //www. ifca. ai/), was held in Tobago, February 12 15, 2007. The conference is a well-established and premier international - rum for research, advanced development, education, exploration, and debate - garding security in the context of ?nance and commerce. We continue to cover all aspects of securing transactions and systems, which this year included a range of technical areas such as cryptography,...