This book constitutes the thoroughly refereed post-conference proceedings of the 5th International Conference on Smart Cities and Green ICT Systems, SMARTGREENS 2017, and the Third International Conference on Vehicle Technology and Intelligent Transport Systems, VEHITS 2017, held in Porto, Portugal in April 2017.The 8 full papers of SMARTGREENS 2017 presented were carefully reviewed and selected from 70 submissions. VEHITS 2017 received 77 paper submissions from which 9 papers were selected and published in this book. The papers reflect topics such as smart cities, energy-aware systems and technologies, sustainable computing and communications, sustainable transportation and smart mobility.