Read the requirements of ISO 27001 Clause 4.3: Determining The Scope Of The Information Security
Management System, which requires the organisation to establish the scope of its ISMS.

“The organisation shall determine the boundaries and applicability of the information security management system to establish its scope.

When determining this scope, the organisation shall consider:

• The external and internal issues referred to in clause 4.1.
• The requirements referred to in clause 4.2; and
• Interfaces and dependency between activities performed by the organisation, and those that are performed by the other organisation.

The scope shall be available as documented information.”

Setting up a scope is the most crucial part of the ISMS, as it is a mandatory document that shall be available as documented information. The main purpose of defining the scope is to understand which information the organisation intends to protect.

According to the standard an organisation while setting up of scope must consider these factors:

• Internal and external issues are defined within the context of the organisation,
• The requirements of the interested parties, and
• Dependencies: Dependencies are the processes or elements which are outside the scope of ISMS. For example if the organisation is outsourcing legal services from a law firm.
• Interfaces: Interfaces are the like boundary wall of you ISMS scope, it defines what processes and elements are within the scope of ISMS or out of it. It’s also important to understand the inputs and outputs using these interfaces.

The point is you must protect the intended information no matter where, how and by whom this information is accessed.