The essence of security controls in every computerized accounting system is to prevent, detect and correct unlawful events or error with the potential to impart negatively on information generated from computerized accounting information systems (CAIS). This book therefore discussed those preventive, detective and corrective controls essential for ensuring the confidentiality, integrity, availability and reliability of information generated from such systems. This book also identified components such as programming languages (PL), Database Management Systems (DBMS) and Cryptographic Mechanisms as essential for developing a Secured CAIS. It was also realised that the successful implementation of a CAIS in organizations are largely influence by some critical factors; these factors are explained in the book. The book closes with a recommendation for ensuring the successful implementation of a Computerized Accounting Information Systems (CAIS)