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T he fifth-generation (5G) wireless system is a major transformation from the current cellular network to a network of everything that connects all people and machines in service-based architecture. Accordingly, the 5G network enforces different performance metrics based on the caller type and service requested. Researchers are aiming to improve the deliverables of enabling technologies such as new radio; massive multiple input, multiple output (mMIMO); mobileedge computing; network virtualization; and more. However, these technologies must be collectively evaluated using end-to-end (E2E) trails to verify the 5G advantages of gigabit downloading speed and ultralow latencies. It is the network slicing and service-based scenarios that drive 5G developers to expand their visions and look beyond the radio access network (RAN) to the 5G core network (5GC). This means that 5GC processing speeds will now need to be considered when evaluating the perfor mance of any 5G service. For instance, vehicleto-everything (V2X) communications need specific time-delay requirements to obtain geolocational data or updates on the status of the next road junction. This type of communication falls under the ultrareliable low-latency communication (URLLC) framework. Enhanced mobile broadband and massive Internet of Things are the other dimensions of 5G that can be identified using standard slice type value. This service-technology association in 5G requires developing new suites of protocols and interfaces to enable ubiquitous efficient connectivity to end users. The 5G system will be an ultradense network (UDN) that deploys a massive number of small cells to utilize spectrum opportunities locally for every single hertz. Considering the large number of cells and physical layer improvements, the 5G network will require an efficient management of resources and operations. Therefore, software-defined networking (SDN) will be an important component for forwarding traffic between the various entities of future networks. To this end, data centers are the platforms that will blend network control with virtual entities for local efficient resource management at different network sites. Thus, it is time to start considering 5G systems as a whole network rather than fragmented technologies. This vision will help researchers fill in the gaps of wireless-system development and meet the goal of establishing a new network that can boost the digital economy and engage the evolution of technology and society. This is the second issue of the IEEE 5G Initiative series in IEEE Vehicular Technology Magazine. The special issues will be published twice a year and cover different 5G development aspects to help the research community gain a better understanding of the latest findings from both academia and industry. This issue has ten articles that address different 5G technologies and approaches. The first article, “Full-Duplex Communications” by Animesh Yadav, Georgios I. Tsiropoulos, and Octavia A. Dobre, studies interference in singleand multismall-cell networks to evaluate the feasibility of full-duplex communications in 5G networks. The authors provide the state of the art for intracell cochannel interference mitigation techniques and characterize the spectral-efficiency gains for mMIMO and millimeter-wave (mm-wave) technologies. Following is the article “Low-Latency C-RAN” by Hong Ren, Nan Liu, Cunhua Pan, Maged Elkashlan, Arumugam Nallanathan, Xiaohu You, and New Considerations for 5G Wireless Systems