ISO 27001 – The comprehensive guide to the ISMS standard

Information security is more important today than ever. Data is the most valuable asset of many companies – and this is precisely where ISO 27001 comes in: It is the globally recognized standard for information security management systems (ISMS).

In this article you will learn:

What ISO 27001 actually is
What advantages does certification offer?
For whom it is relevant
How the certification process works
What costs you have to expect

What is ISO 27001?

ISO/IEC 27001 is an international standard that defines the requirements for an information security management system (ISMS) . Its goal is to systematically protect the confidentiality, integrity, and availability of information .

At the heart of the standard are the security controls described in Appendix A – a total of 114 measures ranging from access controls to incident management to physical security . Which of these must be implemented within the company depends on an individual risk assessment .

The ISMS as a basis

An ISMS is more than just a technical security concept. It is a management system that defines processes, responsibilities, and controls for information security. Companies benefit in several ways:

Risks are systematically identified and reduced
Security incidents can be better managed
Customers, partners and investors gain trust

An ISMS is particularly important for organizations that work with sensitive or personal data – for example, tech startups, banks, or public institutions.

The PDCA cycle – continuous improvement

ISO 27001 is based on the well-known Plan-Do-Check-Act (PDCA) cycle :

Plan – identify risks, set security goals
Do – Implement policies, processes and controls
Check – Check effectiveness and uncover security gaps
Act – Derive measures for optimization

This means that ISO 27001 is not a one-time certification, but an ongoing improvement process .

Benefits of ISO 27001 certification

Certification brings tangible benefits:

Creating trust : Proof for customers and partners that data is handled responsibly
Meet legal requirements : Support with GDPR, NIS2 & Co.
Risk minimization : Protection against cyberattacks and data leaks
Competitive advantage : Often a prerequisite for winning tenders or large customers
Continuous improvement : Security processes are regularly reviewed and optimized

Who needs ISO 27001?

In short: almost every company .

Corporations : due to complex structures and global data flows
SMEs : increasingly affected by cyber risks
Start-ups : Advantage in competition and with investors
Authorities & public sector : because of sensitive citizen data

With the NIS2 Directive, the circle of obligated companies will be significantly larger from 2024 onwards – even many medium-sized companies will then have to demonstrate an ISMS.

The path to ISO 27001 – process and duration

The certification takes place in several phases:

Structure of the ISMS
- Define scope
- Analyze risks
- Define security policies
- Implement processes
- Conduct internal audit
Certification audit
- Stage 1 : Review of documentation
- Stage 2 : On-site review of implementation
Surveillance audits – annually to maintain
Recertification – every three years

The duration is usually between 6 and 18 months .

Costs of ISO 27001 certification

The total costs depend heavily on company size and complexity. Typical factors include:

Certification body : approx. €7,000 per year (including surveillance audits)
Internal effort : employee days for planning, implementation and maintenance
External consulting by YOUR ISMS: guaranteed €11,988.00

Many companies are now relying on automation solutions to reduce costs and speed up the certification process.

The difference at a glance

Characteristic	SOC 2	ISO 27001	TISAX®
scope	Primarily widespread in the USA and North America	Widely used internationally	In the German automotive industry
Introduction and supervision	Introduced by the AICPA (American Institute of Certified Public Accountants)	Introduced by ISO (International Organization for Standardization)	Developed for the automotive industry
Type of standard	Voluntary compliance standard	Voluntary compliance standard	Industry-specific standard
Examination area	Checking a system for external access and changes also includes checking the operational ISMS	Concerns the information security of a company and promotes the establishment of an ISMS	Extends the requirements of ISO 27001 to include specific requirements for the automotive industry
Main goal	Shows that data is kept secure and creates trust among investors and customers	Strengthens information security, minimizes the risk of hacker attacks and increases trust	Provides a review and exchange mechanism for information security in the automotive industry
Risk assessment	Focused on protecting sensitive data and ensuring IT system availability	Based on a risk analysis carried out by the company to determine appropriate protective measures	Takes into account industry-specific requirements and includes the protection of prototypes and trade secrets
Transparency & Responsibility	Creates transparency and emphasizes the responsibility of management and employees	Integrates information security into the corporate culture and requires employee training	Provides transparency and demonstrates that sensitive data is stored securely, especially with regard to automotive manufacturers and suppliers

ISO 27001 compared to SOC 2 and TISAX®

SOC 2 : especially relevant for US SaaS and cloud companies
TISAX® : industry-specific for the automotive industry
ISO 27001 : universally and globally recognized

While SOC 2 focuses more on system controls and TISAX® on automotive-specific requirements , ISO 27001 offers the broadest international framework .

Conclusion

ISO 27001 is the gold standard for information security. It helps companies reduce risks, build trust, and comply with regulatory requirements. While the effort and costs are not insignificant, the benefits far outweigh the risks—especially in a digital world where data is one of the most important assets.