The external ISO is responsible for developing, implementing and monitoring an organisation's information security strategy. This includes identifying risks, implementing security policies and monitoring compliance. The external ISB also acts in an advisory capacity, helping to identify security gaps and propose solutions.
An external ISO is used when a company does not have internal information security expertise or when internal resources are insufficient. Companies that have specific requirements for their IT security (e.g. due to legal requirements or industry-specific standards) also often use external ISOs to ensure that all security measures are implemented correctly.
The external ISO provides an independent and objective view of an organisation's information security. They often have extensive experience of working with different organisations and industries and can therefore integrate best practice. In addition, external ISOs can be engaged on a flexible and as-needed basis, saving costs and resources.
An external ISO should have extensive experience in information security and hold certifications such as CISSP (Certified Information Systems Security Professional), CISM (Certified Information Security Manager) or ISO/IEC 27001 Lead Auditor/Implementer. They should also have up-to-date knowledge of the regulatory framework (e.g. GDPR, NIS2 Directive, DORA Regulation) and industry-specific requirements.
The duration of the implementation depends heavily on the size of the organisation, the complexity of the IT infrastructure and the current state of information security. Typically, the external ISO starts with a comprehensive security analysis, which is used to develop a catalogue of measures. This process can take anywhere from a few weeks to several months. Implementation takes place step by step, with regular progress reports and adjustments.