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Classification of information

13/09/2025

Author: Stuart Barker | ISO 27001 Expert and Thought Leader

The process of putting information into groups based on how sensitive it is. This helps an organisation know how much protection to give each piece of data. It ensures that valuable or private information is kept safe, while public information is easy to share.

Examples

  • Public: A company’s website or a press release. This information is meant for everyone to see.
  • Internal: Employee handbooks or meeting notes. This information is for staff only and shouldn’t be shared outside the company.
  • Confidential: Customer records or financial reports. This is very private data that, if lost, could cause great harm to the company or its clients.

Context

Classifying information is a key step in keeping it secure. It’s like putting different valuables into different kinds of safes. You wouldn’t put a common coin in a high-tech bank vault, just as you wouldn’t leave a precious gem in an open box. This practice helps a business use its security resources wisely. It also makes sure that everyone knows how to handle different types of data correctly.

Relevant ISO 27001 Controls

The following controls from the ISO/IEC 27001:2022 standard are related to classification of information:

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.