This part of the 61850 series introduces the modelling methods, communication principles, and information models that are used in the various parts of the IEC 61850-7-x series. The purpose of this part of the IEC 61850 series is to provide - from a conceptual point of view - assistance to understand the basic modelling concepts and description methods for: - substation-specific information models for power utility automation systems, - device functions used for power utility automation purposes, and - communication systems to provide interoperability within power utility facilities. Furthermore, this part of the IEC 61850 series provides explanations and provides detailed requirements relating to the relation between IEC 61850-7-4, IEC 61850-7-3, IEC 61850-7-2 and IEC 61850-5. This part explains how the abstract services and models of the IEC 61850-7-x series are mapped to concrete communication protocols as defined in IEC 61850-8-1.