Social sustainability today, as the most important dimension of sustainable development, has an important place in urban planning and its importance in planning is constantly increasing with the increase of social problems and divergence between neighborhoods in terms of performance and participation. Therefore, this requires more research in urban studies. This study was conducted to investigate the role of social participation in the development of social sustainability in neighborhoods. For this purpose, the significance of the significant effect of these two variables has been measured. The research is applied in terms of purpose and descriptive-analytical in terms of method. Data collection was library and field method. The statistical population of the study consists of a group of experts who were selected by the available method of 20 people as the sample size of the study. Data collection tool is a questionnaire based on theoretical foundations and studies conducted on a five-point Likert scale. Data analysis was performed using structural equations with the help of Emus software. The results showed that the social participation of citizens in neighborhoods with a coefficient (beta) of 0.732 has a positive effect on sustainable social development of these neighborhoods and the relationship between these two variables is significant. In other words, sustainable social development will be strengthened by strengthening social participation. And the variables of sense of belonging, satisfaction with the neighborhood, participation in neighborhood activities and trust also have a positive effect on the variables of social participation in neighborhoods.

Housing design plays a crucial role in sustainable social development as cities face numerous challenges due to various changes in the physical landscape. Therefore, it is imperative to establish appropriate design indicators for residential towers. This study aims to investigate the design indicators for sustainable social development in residential towers in the metropolis of Tehran. The research method employed is descriptive-analytical and applied in nature. The statistical population for this study consists of architectural experts who are members of the Tehran Organization. According to the Engineering System Organization, the statistical population comprises 22,000 experts and members of the Tehran Engineering System Organization. The sample size was determined to be 384 individuals based on the Morgan table. The results of the Friedman test indicate that designing open spaces for art, culture, games, and entertainment in towers promotes interactions and a sense of belonging, while mitigating the negative effects of industrial life on residents. This aspect was found to have the highest weightage of 17.81. Additionally, the flexibility in tower design and overcoming structural constraints through solutions such as strip design and atrium design, along with facilitating proper access and installation of open spaces, contribute to sustainable development and enhance residents' satisfaction. This indicator obtained a weightage of 17.51. Furthermore, the effective management of towers and the design of suitable social spaces on roofs and ground floors (interactive, sports, cultural, and artistic) have a significant impact on reducing tower-related issues and promoting vitality and public participation. This indicator ranked third with a weightage of 17.42. Consequently, sustainable social development is closely linked to the design of residential towers.