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Information Security Management System (ISMS)

11/09/2025

Author: Stuart Barker | ISO 27001 Expert and Thought Leader

Information Security Management System (ISMS) Definition - ISO 27001 Glossary

An Information Security Management System (ISMS) is a systematic framework of policies, procedures, and controls that an organisation uses to manage and protect its confidential and sensitive information. It is not just an IT system; it is a holistic approach to managing information security risk across the entire organisation. The ISMS is designed to ensure the confidentiality, integrity, and availability (the “CIA triad”) of all information assets, regardless of their format.

Key Components

  • Policies: High-level rules and guidelines set by management.
  • Procedures: Detailed, step-by-step instructions for employees to follow.
  • Controls: Specific technical or organisational measures put in place to manage risk (e.g., firewalls, employee training).

ISO 27001 Context

The ISO 27001 standard provides the detailed requirements for establishing, implementing, maintaining, and continually improving an ISMS. The entire standard is built around this core concept, using the Plan-Do-Check-Act (PDCA) cycle to ensure the system is effective and responsive to new threats and business changes.

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Stuart Barker, ISO 27001 expert

Stuart Barker
ISO 27001 Expert and Thought Leader

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Stuart Barker, ISO 27001 expert

About the author

Stuart Barker is an information security practitioner of over 30 years. He holds an MSc in Software and Systems Security and an undergraduate degree in Software Engineering. He is an ISO 27001 expert and thought leader holding both ISO 27001 Lead Implementer and ISO 27001 Lead Auditor qualifications. In 2010 he started his first cyber security consulting business that he sold in 2018. He worked for over a decade for GE, leading a data governance team across Europe and since then has gone on to deliver hundreds of client engagements and audits.

He regularly mentors and trains professionals on information security and runs a successful ISO 27001 YouTube channel where he shows people how they can implement ISO 27001 themselves. He is passionate that knowledge should not be hoarded and brought to market the first of its kind online ISO 27001 store for all the tools and templates people need when they want to do it themselves.

In his personal life he is an active and a hobbyist kickboxer.

His specialisms are ISO 27001 and SOC 2 and his niche is start up and early stage business.