This paper aims to investigate the impact of vitality on the social values attached to two public squares in London. Based on an extensive review of the literature and empirical work, this paper will explore the similarities and differences between these two squares in order to deliver a better understanding of the reasons behind urban design vitality and quality in generating social values attached to physical spaces. These two squares are comparable in size, physical setting and geographical and social context providing unique contexts for socio-spatial analysis. This study follows a case study approach with a qualitative method. For both case studies, there are 100 surveys and 33 semi-structured interviews in total conducted with participants at the squares. In addition, many site observations for this study have been taken, in both cases, at different times of the day to track human movement, activities, spatial qualities, social interactions and spatial interrelations. This study demonstrates the complex nature of the generation of vitality in urban spaces.