In recent years, sustainability has gained importance across the world. However, the social aspect of the concept has been explored the least. A trend leads towards cities targeting population growth. Densification is often seen as a tool to accommodate for a growing population in a rather sustainable way. This case study focusses on evaluations of Umeå Municipality’s population goal and densification, and on understanding the social sustainability of such strivings. Aiming to explore emotions, attitudes, and beliefs towards the population goal and densification, the study is based on three research questions, concerning: 1) the response towards the population goal and densification in Umeå; 2) the association of beliefs about social capital and equity in the neighborhood and the response towards the population goal and densification; and 3) the relationship between beliefs and emotions evoked by densification and the attitude towards densification. A web survey was carried out investigating people’s responses to the population goal and densification in Umeå, aiming to better understand the social sustainability of such strivings. In this study, social capital and equity were used as indicators for social sustainability. The literature suggests that the influence of density on social equity is predominantly positive, whereas the influence on social capital is ambiguous. More generally, the relationship between densification and social sustainability is seen as complex and context dependent. The survey indicates attitudes towards the population goal being neutral, and towards densification slightly negative. Moreover, it has been found that beliefs concerning the neighborhood influence the perception particularly of densification. Finally, this study shows that emotions play an important role when it comes to the acceptance of densification.