Nearly every MNE group must arrange for a wide scope of services to be available to its members, in particular administrative, technical, financial and commercial services. Such services may include management, coordination and control functions for the whole group. The cost of providing such services may be borne initially by the parent, by one or more specially designated group members (“a group service centre”), or other group members. An independent enterprise in need of a service may acquire the services from a service provider who specialises in that type of service or may perform the service for itself (i.e. in-house). In a similar way, a member of an MNE group in need of a service may acquire it from independent enterprises, or from one or more associated enterprises in the same MNE group (i.e. intra-group), or may perform the service for itself. Intra-group services often include those that are typically available externally from independent enterprises (such as legal and accounting services), in addition to those that are ordinarily performed internally (e.g. by an enterprise for itself, such as central auditing, financing advice, or training of personnel). It is not in the interests of an MNE group to incur costs unnecessarily, and it is in the interest of an MNE group to provide intra-group services efficiently. Application of the guidance in this chapter should ensure that services are appropriately identified and associated costs appropriately allocated within the MNE group in accordance with the arm’s length principle.