ISO 27001

An Introduction To ISO 27001

The ISO 27001 standard was published in October 2005, essentially replacing the old BS7799-2 standard. It is the specification for an ISMS, an Information Security Management System. BS7799 itself was a long standing standard, first published in the nineties as a code of practice. As this matured, a second part emerged to cover management systems. It is this against which certification is granted. Today in excess of a thousand certificates are in place, across the world.

On publication, ISO 27001 enhanced the content of BS7799-2 and harmonized it with other standards. A scheme was been introduced by various certification bodies for conversion from BS7799 certification to ISO27001 certification.

The objective of the standard itself is to “provide requirements for establishing, implementing, maintaining and continuously improving an Information Security Management System (ISMS)”. Regarding its adoption, this should be a strategic decision. Further, “The design and implementation of an organization’s information security management system is influenced by the organization’s needs and objectives, security requirements, the organizational processes used and the size and structure of the organization”.

The 2005 version of the standard heavily employed the PDCA, Plan-Do-Check-Act model to structure the processes, and reflect the principles set out in the OECG guidelines (see oecd.org). However, the latest, 2013 version, places more emphasis on measuring and evaluating how well an organisation’s ISMS is performing. A section on outsourcing was also added with this release, and additional attention was paid to the organisational context of information security.

The ISO27001 Certification Process

Some of the most common questions pertaining to the 27000 series of standards relate to the certification process for ISO27001. This page is intended to help address some of these.

In a nutshell, the following diagram explains the logical flow of the process itself:

ISO27001 Certification Process


The process starts when the organization makes the decision to embark upon the exercise. Clearly, at this point, it is also important to ensure management commitment and then assign responsibilities for the project itself.

An organizational top level policy can then be developed and published. This can, and will normally, be supported by subordinate policies. The next stage is particularly critical: scoping. This will define which part(s) of the organization will be covered by the ISMS. Typically, it will define the location, assets and technology to be included.

At this stage a risk assessment will be undertaken, to determine the organization’s risk exposure/profile, and identify the best route to address this. The document produced will be the basis for the next stage, which will be the management of those risks. A part of this process will be selection of appropriate controls with respect to those outlined in the standard (and ISO27002), with the justification for each decision recorded in a Statement of Applicability (SOA). The controls themselves should then be implemented as appropriate.

The certification process itself can then be embarked upon via a suitable accredited third party