ISO/IEC TR 15067-3-8:2020(E), which is a Technical Report, provides a conceptual framework for developing architectures and designing solutions related to transactive energy (TE). Transactive energy allows electricity generated locally by consumers using wind, solar, storage, etc., at homes or buildings to be sold into a competitive market. This document provides guidance for enhancing interoperability among distributed energy resources involved in energy management systems at homes and buildings. It addresses gaps identified as problematic for the industry by providing definitions of terms, architectural principles and guidelines, and other descriptive elements that present a common ground for all interested parties to discuss and advance TE. This document builds upon ISO/IEC 15067-3, with technology to accommodate a market for buying and selling electricity generated centrally or locally by consumers. The energy management agent (EMA) specified in ISO/IEC 15067-3 can represent the customer as a participant in TE. Transactive energy is important for achieving electric grid stability as power from renewable sources such as wind and solar fluctuates with time and weather.