This level of architecture is defined in the common approach to Federal Enterprise Architecture Framework and focuses on a system or service in one particular mission sector of the Executive Branch of the U.S. Federal Government. These inter-agency architectures often include the enablement of mission and/or support shared services, wherein the roles of provider and consumer need to be detailed and a comprehensive business model for the service provides the requirements for the architecture. These architectures may also include private sector participants.

Source: See Federal Enterprise Architecture Framework (common approach - as explained in Collaborative Planning Methodology).