ISO 27001:2022 Annex A 5.15 – Access Control Explained

Access control is where policy, people, and technology meet.

Annex A 5.15 exists to ensure organisations control who has access to information and associated assets, and that access is aligned with business need and risk. Poor access control is one of the most common root causes of security incidents, not because controls are missing, but because they are poorly designed or inconsistently applied.

This control sets the foundation for effective identity, authentication, and access management across the organisation.

ISO 27001

Quick Guide: Annex A 5.15 at a Glance

Annex A 5.15 of ISO 27001:2022 focuses on establishing and applying access control rules.

At a practical level, this means:

  • Defining how access to information and assets is controlled
  • Ensuring access aligns with job roles and responsibilities
  • Applying the principle of least access
  • Managing both physical and logical access
  • Reviewing access as roles and circumstances change

The control does not mandate a specific access control model or technology. It expects organisations to apply risk-based, proportionate access control that reflects how information is used.

In-Depth Guide to Annex A 5.15

What Is Annex A 5.15 and Why Does It Matter?

Access control answers a simple question:

Who can access what, and why?

Without clear access control:

  • People accumulate access they no longer need
  • Privileged access goes unchecked
  • Sensitive information is exposed unnecessarily
  • Accountability becomes unclear

Annex A 5.15 ensures access is deliberate, justified, and controlled, rather than inherited, assumed, or forgotten.

It applies to:

  • Information
  • Systems and applications
  • Networks and services
  • Physical locations

Consistency across these areas is key.

How to Implement Annex A 5.15 Effectively

A pragmatic approach to Annex A 5.15 typically includes the following elements.

1. Define an Access Control Approach

Organisations should define how access decisions are made, including:

  • Criteria for granting access
  • How access aligns with job roles
  • How conflicts of interest are avoided

This provides a consistent basis for decisions.

2. Apply the Principle of Least Access

Access should be limited to what is necessary to perform assigned duties.

This reduces:

  • Exposure of sensitive information
  • Impact of compromised accounts
  • Risk associated with insider misuse

Least access supports both security and accountability.

3. Manage Privileged Access Carefully

Privileged access carries increased risk.

Organisations typically:

  • Restrict privileged access to a small number of roles
  • Apply additional oversight or monitoring
  • Review privileged access more frequently

Privilege should be treated as an exception, not a default.

4. Control Access to Networks and Services

Users should only have access to:

  • Networks
  • Network services
  • Systems

that are required for their role.

This includes considering remote access, shared services, and third-party connectivity.

5. Review Access When Circumstances Change

Access control is not static.

Reviews are commonly triggered by:

  • Role changes
  • Transfers or promotions
  • Temporary assignments
  • Exit from the organisation

Timely review prevents access from persisting beyond need.

In-Depth Guide to Annex A 5.1

What is Annex A 5.1 and Why Does It Matter?

  • What the organisation values
  • How security decisions are approached
  • Where accountability sits
  • Aligns security with business objectives
  • Supports proportionate, risk-based decisions
  • Provides a reference point during incidents and disputes
  • Creates consistency without bureaucracy

How to Implement Annex A 5.1 Effectively

1. Define a Comprehensive Information Security Policy
  • Scope: What the policy applies to (systems, data, people).
  • Objectives: Why security is important for the business.
  • Roles & Responsibilities: Who is accountable for security.
  • Key Principles: Risk management, access control, and data protection.
2. Secure Senior Management Approval
  • Review and approve policies.
  • Ensure resources are allocated for implementation.
  • Lead by example in enforcing security policies.
3. Communicate and Train Employees
  • Include security policies in onboarding and ongoing training.
  • Ensure policies are easily accessible to all employees.
  • Encourage acknowledgment and acceptance of security responsibilities.
4. Regular Review & Continuous Improvement
  • Set a schedule for periodic policy reviews (at least annually).
  • Update policies based on business changes, new threats, or regulatory updates.
  • Conduct audits to ensure compliance and effectiveness.
5. Integrate Policies into the ISMS
  • Use it to develop more detailed security procedures.
  • Ensure policies align with other Annex A controls and broader risk management practices.
Key Differences: ISO 27001:2013 vs ISO 27001:2022
AspectISO 27001:2013ISO 27001:2022
Control StructureTwo separate controls: 5.1.1 & 5.1.2Merged into one control (5.1)
Implementation GuidanceLess prescriptiveMore detailed guidance for policy creation and alignment
Awareness & TrainingNot explicitly mentionedExplicitly requires policies to be part of training programmes
Attributes TableNot includedew attributes table for mapping policies to industry terms
Common Challenges & How to Overcome Them
  • Challenge: Employees don’t follow security policies.
  • Solution: Make policies practical and relevant to daily work. Use real-world examples in training.
  • Challenge: Policies are outdated or too generic.
  • Solution: Schedule annual reviews and update policies based on real threats and business changes.
  • Challenge: Policies are written in technical jargon.
  • Solution: Use plain language that all employees can understand.
  • Challenge: Lack of leadership buy-in.
  • Solution: Show how weak security affects business objectives—costs of breaches, loss of client trust, and legal penalties.
Final Recommendations
  • Make security policies living documents—review, refine, and update regularly.
  • Use policy training and awareness to create a security-conscious workforce.
  • Ensure policies are accessible, relevant, and easy to understand.
  • Keep policies aligned with business strategy and regulatory requirements.
  • Engage leadership in driving security culture from the top down.

Common Challenges and How to Overcome Them

  • Granting broad access “just in case”
  • Use role-based or need-based access decisions
  • Poor visibility of privileged access
  • Identify, restrict, and review elevated access
  • Access not reviewed after role changes
  • Tie access reviews to HR and operational processes
  • Inconsistent access rules across systems
  • Apply common principles, even if tools differ

Access control fails most often through drift, not design.

In-Depth Guide to Annex A 5.1

What is Annex A 5.1 and Why Does It Matter?

  • What the organisation values
  • How security decisions are approached
  • Where accountability sits
  • Aligns security with business objectives
  • Supports proportionate, risk-based decisions
  • Provides a reference point during incidents and disputes
  • Creates consistency without bureaucracy

How to Implement Annex A 5.1 Effectively

1. Define a Comprehensive Information Security Policy
  • Scope: What the policy applies to (systems, data, people).
  • Objectives: Why security is important for the business.
  • Roles & Responsibilities: Who is accountable for security.
  • Key Principles: Risk management, access control, and data protection.
2. Secure Senior Management Approval
  • Review and approve policies.
  • Ensure resources are allocated for implementation.
  • Lead by example in enforcing security policies.
3. Communicate and Train Employees
  • Include security policies in onboarding and ongoing training.
  • Ensure policies are easily accessible to all employees.
  • Encourage acknowledgment and acceptance of security responsibilities.
4. Regular Review & Continuous Improvement
  • Set a schedule for periodic policy reviews (at least annually).
  • Update policies based on business changes, new threats, or regulatory updates.
  • Conduct audits to ensure compliance and effectiveness.
5. Integrate Policies into the ISMS
  • Use it to develop more detailed security procedures.
  • Ensure policies align with other Annex A controls and broader risk management practices.
Key Differences: ISO 27001:2013 vs ISO 27001:2022
AspectISO 27001:2013ISO 27001:2022
Control StructureTwo separate controls: 5.1.1 & 5.1.2Merged into one control (5.1)
Implementation GuidanceLess prescriptiveMore detailed guidance for policy creation and alignment
Awareness & TrainingNot explicitly mentionedExplicitly requires policies to be part of training programmes
Attributes TableNot includedew attributes table for mapping policies to industry terms
Common Challenges & How to Overcome Them
  • Challenge: Employees don’t follow security policies.
  • Solution: Make policies practical and relevant to daily work. Use real-world examples in training.
  • Challenge: Policies are outdated or too generic.
  • Solution: Schedule annual reviews and update policies based on real threats and business changes.
  • Challenge: Policies are written in technical jargon.
  • Solution: Use plain language that all employees can understand.
  • Challenge: Lack of leadership buy-in.
  • Solution: Show how weak security affects business objectives—costs of breaches, loss of client trust, and legal penalties.
Final Recommendations
  • Make security policies living documents—review, refine, and update regularly.
  • Use policy training and awareness to create a security-conscious workforce.
  • Ensure policies are accessible, relevant, and easy to understand.
  • Keep policies aligned with business strategy and regulatory requirements.
  • Engage leadership in driving security culture from the top down.

Final Recommendations

Annex A 5.15 is about controlling access deliberately and consistently.

When access control is implemented effectively:

  • Unauthorised access risk is reduced
  • Sensitive information is better protected
  • Accountability is clearer
  • Other access-related controls work more effectively

Access control does not need to be complex. It needs to be clear, enforced, and reviewed.

That is the outcome Annex A 5.15 is designed to achieve.

In-Depth Guide to Annex A 5.1

What is Annex A 5.1 and Why Does It Matter?

  • What the organisation values
  • How security decisions are approached
  • Where accountability sits
  • Aligns security with business objectives
  • Supports proportionate, risk-based decisions
  • Provides a reference point during incidents and disputes
  • Creates consistency without bureaucracy

How to Implement Annex A 5.1 Effectively

1. Define a Comprehensive Information Security Policy
  • Scope: What the policy applies to (systems, data, people).
  • Objectives: Why security is important for the business.
  • Roles & Responsibilities: Who is accountable for security.
  • Key Principles: Risk management, access control, and data protection.
2. Secure Senior Management Approval
  • Review and approve policies.
  • Ensure resources are allocated for implementation.
  • Lead by example in enforcing security policies.
3. Communicate and Train Employees
  • Include security policies in onboarding and ongoing training.
  • Ensure policies are easily accessible to all employees.
  • Encourage acknowledgment and acceptance of security responsibilities.
4. Regular Review & Continuous Improvement
  • Set a schedule for periodic policy reviews (at least annually).
  • Update policies based on business changes, new threats, or regulatory updates.
  • Conduct audits to ensure compliance and effectiveness.
5. Integrate Policies into the ISMS
  • Use it to develop more detailed security procedures.
  • Ensure policies align with other Annex A controls and broader risk management practices.
Key Differences: ISO 27001:2013 vs ISO 27001:2022
AspectISO 27001:2013ISO 27001:2022
Control StructureTwo separate controls: 5.1.1 & 5.1.2Merged into one control (5.1)
Implementation GuidanceLess prescriptiveMore detailed guidance for policy creation and alignment
Awareness & TrainingNot explicitly mentionedExplicitly requires policies to be part of training programmes
Attributes TableNot includedew attributes table for mapping policies to industry terms
Common Challenges & How to Overcome Them
  • Challenge: Employees don’t follow security policies.
  • Solution: Make policies practical and relevant to daily work. Use real-world examples in training.
  • Challenge: Policies are outdated or too generic.
  • Solution: Schedule annual reviews and update policies based on real threats and business changes.
  • Challenge: Policies are written in technical jargon.
  • Solution: Use plain language that all employees can understand.
  • Challenge: Lack of leadership buy-in.
  • Solution: Show how weak security affects business objectives—costs of breaches, loss of client trust, and legal penalties.
Final Recommendations
  • Make security policies living documents—review, refine, and update regularly.
  • Use policy training and awareness to create a security-conscious workforce.
  • Ensure policies are accessible, relevant, and easy to understand.
  • Keep policies aligned with business strategy and regulatory requirements.
  • Engage leadership in driving security culture from the top down.

The Annex Control Table

ISO 27001:2022 Organisational Controls
ISO 27001:2022 Technological Controls