The 14th International Conference on Urban Regeneration and Sustainability addresses all aspects of the urban environment aiming to provide solutions leading towards sustainability. The Sustainable City 2020 conference follows a series of very successful meetings that started in Rio (2000), followed by Segovia (2002), Siena (2004), Tallinn (2006), Skiathos (2008), A Coruña (2010), Ancona (2012), Kuala Lumpur (2013), Siena (2014), Medellin (2015), Alicante (2016), Seville (2017) and Valencia (2019). The meeting always attracts a substantial number of contributions from participants from different backgrounds and countries. The variety of topics and experiences is one of the main reasons behind the success of the series. Urban areas result in a series of environmental challenges varying from the consumption of natural resources and the subsequent generation of waste and pollution, contributing to the development of social and economic imbalances. As cities continue to grow all over the world, these problems tend to become more acute and require the development of new solutions. The challenge of planning sustainable contemporary cities lies in considering the dynamics of urban systems, exchange of energy and matter, and the function and maintenance of ordered structures directly or indirectly supplied and maintained by natural systems. The task of researchers, aware of the complexity of the contemporary city, is to improve the capacity to manage human activities, pursuing welfare and prosperity in the urban environment. Any investigation or planning on a city ought to consider the relationships between the parts and their connections with the living world. The dynamics of its networks (flows of energy-matter, people, goods, information and other resources) are fundamental for an understanding of the evolving nature of today’s cities. Large cities are probably the most complex mechanisms to manage. They represent a fertile ground for architects, engineers, city planners, social and political scientists, and other professionals able to conceive new ideas and time them according to technological advances and human requirements. The Sustainable City Conference addresses the multidisciplinary components of urban planning, the challenges presented by the increasing size of the cities, the number of resources required and the complexity of modern society.