Abstract. In this paper we define what is a Sociable Smart City and how this vision can be realised. This vision elaborates on recent developments in smart cities around the world where novel technologies and applications have been introduced in order to provide services and promote economic growth and sustainability. According to our approach a smart city has to also focus on social and cultural aspects, to allow people to interact with their cities in novel ways and to enable them to shape and decide the future of the city. This approach has originated from the large-scale deployment and evaluation of the CLIO urban computing system, which enables people to interact with the collective city memory. Our findings revealed that a system that exploits city infrastructure and both people's and artificial intelligence in order to empower and engage them in social activities may enhance citizen participation and sense of belonging as well as it may enable urban social interactions. Aiming to address the Sociable Smart City vision, we held a homonymous workshop in 2013 that brought together researchers of urban computing, smart cities, pervasive technologies and hci. Among its outcomes has been a definition of the Sociable Smart City, the identification of challenges in realising it, the proposition of applications that can accelerate its adoption and what their impact can be, as well as the identification of the major stakeholders involved.