Biometric authentication is increasingly gaining popularity in a large spectrum ofapplications,rangingfromgovernmentprograms(e. g.,nationalIDcards,visas for international travel,and the?ght against terrorism) to personal applications such as logical and physical access control. Although a number of e?ective - lutions are currently available, new approaches and techniques are necessary to overcomesomeofthelimitationsofcurrentsystemsandtoopenupnewfrontiers in biometric research and development. The 30 papers presented at Biometric Authentication Workshop 2004 (BioAW 2004) provided a snapshot of current research in biometrics, and identify some new trends. This volume is composed of?vesections:facerecognition,?ngerprintrecognition,templateprotectionand security, other biometrics, and fusion and multimodal biometrics. For classical biometrics like?ngerprint and face recognition, most of the papers in Sect. 1 and 2 address robustness issues in order to make the biometric systems work in suboptimal conditions: examples include face detection and recognition - der uncontrolled lighting and pose variations, and?ngerprint matching in the case of severe skin distortion. Benchmarking and interoperability of sensors and liveness detection are also topics of primary interest for?ngerprint-based s- tems. Biometrics alone is not the solution for complex security problems. Some of the papers in Sect. 3 focus on designing secure systems; this requires dealing with safe template storage, checking data integrity, and implementing solutions in a privacy-preserving fashion. The match-on-tokens approach, provided that current accuracy and cost limitations can be satisfactorily solved by using new algorithms and hardware, is certainly a promising alternative. The use of new biometric indicators like eye movement, 3D?nger shape, and soft traits (e. g.