The article is aimed to discuss and reconsider the concept and challenges of the social housing in the world and in Lithuania. The research consists of three major parts. In the first part the evolution of social housing from the 18th century until nowadays was analyzed and evaluated and eight main trends of architectural expression of social housing were distinguished and shortly characterized. The second part was devoted to the introduction of the dimension of sustainability in the design of affordable housing. The idea of sustainable architecture and the trends of its expression were presented and the composite trends of social housing in urban settings with dimensions of sustainability were formulated and characterized. The third part of the research dealt with the local specifics of the city of Kaunas: the possibilities of localization of the social housing of different trends were analyzed and the experimental design of the social housing complex demonstrating the possibilities of application of environmentally friendly technologies and the potential of rehabilitation of neglected urban areas was shortly presented.
