Definition of Social Sustainability

Social sustainability can be defined as  a life-enhancing condition within communities, and a process within communities that can achieve that condition (McKenzie, 2004)

OR from a section of the definition by the Oxford Institute for Sustainable Development: 

Social sustainability blends traditional social policy areas and principles, such as equity and health, with emerging issues concerning participation, needs, social capital, the economy, the environment, and more recently, with the notions of happiness, wellbeing and quality of life

Colantonio, A. and Dixon, T. (2009) Measuring Socially Sustainable Urban Regeneration in  
  Europe, Oxford Brookes University: Oxford Institute for Sustainable Development (OISD)

what will we focus on?

Maybe on friendly behaviour, that is behaviour that promotes the creation of strong social networks, which not only provides benefits like a sense of belonging, and increased access to local information, but can increase a community´s opportunity to successfully pursue common goals, and according to Michael Woolcock, a senior Social Scientist at the World Bank and a lecturer in Public Policy at
Harvard University, well-connected inddividuals have an increased likelyhood of being hired, housed, healthy and happy. All important elements of Social Sustainability.

Woolcock, M. (2001) ‘The place of social capital in understanding social and economic    
  outcomes’, Canadian Journal of Policy Research, 2 (1), pp. 11-17