A practical and complete guide to ISO/IEC 27001 Compliance

ISO/IEC 27001 is an international standard for information security management. It defines how an organization should identify, manage, and reduce information security risks through a formal framework called an Information Security Management System (ISMS).

Unlike SOC 2, ISO 27001 results in a certification, issued by an accredited certification body, confirming that your organization operates a structured and risk-based security program.

ISO 27001 is widely recognized across Europe and international markets and is often required by enterprise customers, partners, and regulators.

An ISMS is the core of ISO 27001. It is not a tool or a checklist. It is a management system that defines how your company governs information security over time.

An ISMS includes:

• • A formal risk assessment process
• • Security policies and procedures
• • Defined roles and responsibilities
• • Risk treatment and control selection
• • Continuous monitoring and improvement

The goal is not perfection, but consistent and measurable risk management.

Yes. ISO 27001 is a certification, not a report.

After a successful audit, you receive:

• • An ISO 27001 certificate
• • Valid for three years
• • With annual surveillance audits

This certificate proves that your ISMS meets the ISO 27001 standard.

ISO 27001 is risk-based, not prescriptive.

It requires you to:

• • Identify information security risks
• • Evaluate their likelihood and impact
• • Define how you will treat those risks
• • Implement appropriate controls
• • Continuously review and improve

The standard includes Annex A, a list of suggested security controls (access control, incident management, supplier security, etc.), but you are not required to implement all of them—only those relevant to your risks.

Not exactly.

ISO 27001 focuses more on:

• • Governance
• • Risk management
• • Policies and processes
• • Accountability and documentation

Technical controls (like encryption, vulnerability management, or penetration testing) are included only if your risk assessment justifies them.

This makes ISO 27001 flexible, but also easy to misunderstand.

No, penetration testing is not explicitly required by ISO 27001.

However, for most tech-driven companies, it is strongly expected.

ISO 27001 requires you to address technical vulnerabilities identified during your risk assessment. A penetration test is one of the most effective and widely accepted ways to demonstrate that you are doing so.

Because it provides:

• • Strong evidence of technical security maturity
• • Clear validation of controls in real-world conditions
• • Credibility with auditors and enterprise customers

While alternatives exist (vulnerability scanning, code reviews, architecture reviews), penetration tests often offer the clearest and most defensible proof of risk treatment.

If you rely on penetration testing as a risk control, best practice is:

• • Once per year
• • After major infrastructure or application changes

Auditors will expect to see consistency and follow-up, not perfection.

That is normal and expected.

Auditors will look for:

• • The penetration test report
• • A remediation plan
• • Evidence that issues were fixed or formally accepted as risks

A report with findings is not a problem. A lack of follow-up is.

For most small and mid-sized companies:

• • 3 to 6 months is typical
• • Complex organizations may take longer

The timeline depends on:

• • Existing security maturity
• • Documentation quality
• • Team availability
• • Audit readiness

Building an ISMS from scratch is a significant effort if done internally.

The direct certification audit cost is usually reasonable.

The real cost comes from:

• • Internal time and coordination
• • Writing and maintaining documentation
• • Running risk assessments
• • Preparing for audits

For small teams, this often becomes a hidden operational burden.

ISO 27001 is commonly required when:

• • Selling to European or international enterprises
• • Operating in regulated industries
• • Responding to formal vendor security assessments
• • Demonstrating long-term security governance

Unlike SOC 2, ISO 27001 is often less about one deal and more about scaling trust globally.

• • ISO 27001 certifies your security management system
• • SOC 2 provides a detailed report on specific security controls

They are built on similar principles but are not interchangeable. Customers usually ask for one or the other based on geography and expectations.

Yes and many growing companies do.

A common path is:

• • SOC 2 first (North America)
• • ISO 27001 later (international expansion)

Much of the underlying work overlaps, which makes the second framework easier if the first is done properly.

Most companies choose between three approaches:

The right choice depends on your team's capacity and priorities.

It can be, at the right time.

ISO 27001 is most valuable when:

• • Customers explicitly ask for it
• • You operate internationally
• • You want to professionalize security governance early

Doing it too early, without stable systems or customer demand, often wastes effort.

Probo provides a done-for-you ISO 27001 service, supported by a compliance platform:

• • We design and implement your ISMS based on your real risks and workflows
• • We provide the tooling to centralize documentation, risks, and evidence
• • We write and maintain policies, risk assessments, and inventories
• • We manage the certification audit end-to-end
• • We minimize disruption to your engineering and operations teams

Probo acts as your compliance team.