Book excerpt: Enhanced Methods in Computer Security, Biometric and Artificial Intelligence Systems contains over 30 contributions from leading European researchers showing the present state and future directions of computer science research. "Methods of Artificial Intelligence and Intelligent Agents" contains 13 contributions analyzing such areas of AI as fuzzy set theory, predicate logic, neural networks, clustering, data mining and others. It also presents applications of AI as possible solutions for problems like firm bankruptcy, soil erosion, flight control and others. "Information Technology Security" covers three important areas of security engineering in information systems: software security, public key infrastructure and the design of new cryptographic protocols and algorithms. "Biometric Systems" comprises 11 contributions dealing with face picture analysis and recognition systems. This chapter focuses on known methods of biometric problem solution as well as the design of new models.