This document serves as a comprehensive guide on Information Security Management Systems (ISMS) based on ISO/IEC 27001:2005. It emphasizes the importance of properly protecting information as a vital organizational asset and outlines key components such as risk management, security strategies involving people, processes, and technology, and the necessity of compliance with international standards. Additionally, it discusses the roles of various stakeholders in information security, classifications of information assets, and the overarching aim of maintaining confidentiality, integrity, and availability of information.