Biometrics refers to methods for uniquely recognising humans based upon one or more intrinsic physical or behavioural traits. In information technology in particular, biometrics is used as a form of identity access management and access control. It is also used to identify individuals in groups that are under surveillance. Biometric characteristics can be divided in two main classes: physiological and behavioural. Physiological examples include fingerprints, face recognition, DNA, hand and palm geometry, iris recognition, which has largely replaced retina, and odour/scent. Behavioural examples include typing rhythm, gait, and voice. This book gathers the latest research in the field of biometrics and focuses on topics such as on-line signature verification, improving the performance of colour spaces in face recognition, block coding schemes designed for biometrical authentication, large scale palm print identification and distributional properties of count outcomes and limitations of relying on more traditional analytic methods to analyse low base rate occurrences.