This thesis investigates whether higher urban densities and redevelopment projects contribute to more sustainable cities and communities, focusing specifically on Oslo. Recent decades have seen Oslo's strategic push towards densification in central-eastern post-industrial areas, such as Grünerløkka, Tøyen, and Hovinbyen. While this has led to revitalisation, it has also resulted in gentrification and the displacement of long-standing residents. This research highlights the complex interplay between the benefits of urban revitalisation and the negative socio-economic consequences, particularly regarding housing affordability and social equity. Employing a mixed-methods approach, the study integrates qualitative and quantitative methods to provide a comprehensive analysis of the socioeconomic effects and housing dynamics within the context of urban densification. The research is structured along four lines of inquiry: a literature review of the advantages and disadvantages of urban densification, an examination of socio-economic segregation within Oslo, an exploration of Oslo’s densification and housing policies, and a detailed case study of the neighbourhoods that were targeted for densification and redevelopment. By comparing empirical data with planning practices, the study identifies discrepancies between Oslo's goals of sustainable development and the negative socioeconomic outcomes, particularly in rapidly transforming areas of the city. Moreover, the findings illustrate how Oslo’s market-driven housing system often prioritises investment returns over social inclusivity, underestimating the adverse social impacts of higher density, particularly in relation to affordable housing and social inclusion. This thesis underscores the importance of inclusive planning practices that address the marginalisation of lower-income residents and foster a more cohesive and equitable urban environment, ensuring that all residents can benefit from improvements to an area without being economically displaced.