Editorial Green Communication and Networking Yongpeng Wu , 1 Fuhui Zhou, 2 Zan Li , 3 Shunqing Zhang, 4 Zheng Chu, 5 and Wolfgang H. Gerstacker 6 1 Shanghai Key Laboratory of Navigation and Location Based Services, Shanghai Jiao Tong University, Minhang, 200240, China 2 Te School of Information Engineering, Nanchang University, 330031, China 3 Te Integrated Service Networks Lab of Xidian University, Xi’an, 710071, China 4 Te Shanghai Institute for Advanced Communication and Data Science, Shanghai University, Shanghai, 200444, China 5 Te 5G Innovation Centre, Institute for Communication Systems, University of Surrey, Guildford GU2 7XH, UK 6 Te Institute for Digital Communications of Friedrich-Alexander University, Erlangen, 91054, Germany Correspondence should be addressed to Yongpeng Wu; yongpeng.wu2016@gmail.com Received 13 August 2018; Accepted 13 August 2018; Published 2 September 2018 Copyright © 2018 Yongpeng Wu et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Energy crisis and rising concerns on Greenhouse Gas (GHG) emissions have always been crucial issues faced by the devel- opment of wireless communication techniques. As a more energy-efcient network architecture, green communications and networks (GCN) have recently attracted signifcant attention from academia and industry. In particular, the newly designed GCN not only can alleviate the greenhouse efect and decrease the operational expenditure but also can attain sustainable development due to the descending independence on fossil fuel and the exploitation of renewable energy resources. In order to enable the technical and economical GCNs, several emerging techniques have been proposed including energy-efcient and energy harvesting techniques. Although these emerging techniques have drawn considerable attention and have been studied recently, there are still many open theoretical and practical problems to be addressed. Specifcally, most of the existing works have focused on optimizing a single objective of GCNs, such as energy efciency. Since there are multiple conficting objec- tives in GCNs, e.g., spectral efciency and energy efciency, multiobjective strategies are required to be in order to achieve a good tradeof among the conficting objectives. Moreover, since considered nonorthogonal multiple access techniques have advantages in energy efciency and massive connectiv- ity, how to apply nonorthogonal multiple access techniques into GCNs needs to be further investigated. Furthermore, the conventional linear energy harvesting model is ideal in practice. How to design GCNs under practical nonlinear energy harvesting models is required to be focused. Tis special issue aims to provide a comprehensive overview of the state of the art in theory and practice for realizing GCNs, which will bring together researchers from academia, industry, and governmental agencies to promote the research and development needed to address the major challenges that pertain to this cutting-edge research topic. (i) Mutliobjective resource allocation strategies for GCNs (ii) Mutliobjective optimization theory for GCNs (iii) Mutliobjective energy-efcient techniques for GCNs (iv) Energy-efcient cooperative techniques for GCNs (v) Energy-efcient nonorthogonal multiple access tech- niques for GCNs (vi) Practical energy harvesting models for GCNs (vii) Resource optimization for GCNs under practical nonlinear energy harvesting models (viii) Physical layer security techniques for GCNs (ix) Multiantenna techniques for GCNs Twenty-fve papers were submitted for this special issue. Our distinguished reviewers from respective research felds narrowed the feld to fourteen papers which were fnally Hindawi Wireless Communications and Mobile Computing Volume 2018, Article ID 1921353, 3 pages https://doi.org/10.1155/2018/1921353