Book excerpt: This book deals with "crypto-biometrics", a relatively new and multi-disciplinary area of research (started in 1998). Combining biometrics and cryptography provides multiple advantages, such as, revocability, template diversity, better verification accuracy, and generation of cryptographically usable keys that are strongly linked to the user identity. In this text, a thorough review of the subject is provided and then some of the main categories are illustrated with recently proposed systems by the authors. Beginning with the basics, this text deals with various aspects of crypto-biometrics, including review, cancelable biometrics, cryptographic key generation from biometrics, and crypto-biometric key sharing protocols. Because of the thorough treatment of the topic, this text will be highly beneficial to researchers and industry professionals in information security and privacy. Table of Contents: Introduction / Cancelable Biometric System / Cryptographic Key Regeneration Using Biometrics / Biometrics-Based Secure Authentication Protocols / Concluding Remarks