This book constitutes the refereed proceedings of the International Conference on Biometrics, ICB 2006, held in Hong Kong, China in January 2006. The 104 revised full papers presented were carefully reviewed and selected from 192 submissions. Biometric criteria covered by the papers are assigned to face, fingerprint, iris, speech and signature, biometric fusion and performance evaluation, gait, keystrokes, and others. In addition, the results of the Face Authentication Competition (FAC 2006) are also announced in this volume.