This article aims to contribute to the continued development of a coherent theory and practical implementation of sustainable development in the social context. It does so by presenting a systematic discussion on 'social capital', 'social capacity' and 'social carrying capacity' under the umbrella of environmental carrying capacity regarding environmental sustainability. Based on an in-depth literature review, the relationship between social capital and human capital is assessed in detail, the overlap between the social capacity approach and different capability approaches closely discussed and the use as well as the meaning of social carrying capacity in science and in practice for environmental sustainability is more intensively explored. In summary, the results of the analysis provide for all the three assessed terms an innovative variety of possible new contributions to future policy proposals and research priorities for social sustainability regarding population growth, social riots, overwork and technical overload obeying the environmental limits. © 2013 Elsevier Ltd.