The 5G architecture has gone through a major facelift compared to any of the previous mobile communications generations. Many new concepts are introduced, from which the most significant ones are the network virtualization and edge computing, whereas the radio interface are built newly via more advanced modulation schemes and advanced multi-array intelligent antenna solutions. This chapter presents the 5G architecture with some of the most relevant scenarios in roaming and nonroaming environments. It also presents the default 5G architecture with new and reutilized elements, connected and cooperative networks, aggregated services, and key functions of evolved networks. The chapter describes the new aspects of 5G by presenting insights to key items. It includes description and analysis for the SW defined networking, network function virtualization, small cells, evolved HetNet, cloud-based functions, cognitive radio, white-space solutions, and evolved broadcast techniques.