S2CT (Smart Sustainable City Technologies) conference focuses on utilizing the transformational power of Information and Communication Technologies (ICT) for making our urban environment more sustainable, increasing quality of life and efficiency of urban operation and services, and competitiveness while meeting the needs of present and future generations with respect to economic, social and environmental aspects. This year, S2CT 2015 will be collocated with Smart City 360 Summit at Toronto, Canada, from October 13-16, and dedicated to the role of open access platforms, and research and development on sustainable smart city ecosystems. Latest outcome of these enabling technologies will offer plenty of opportunities for policy-makers, research institutes and business to learn, share, and collect experience and best practices of using ICT to plan and operate sustainable urban communities. Scientific results, design concepts and technical solutions will be presented, as well as approaches, and professional experiences.