Psychological needs and human wellbeing are aspects of sustainability that urgently need to be reconsidered in architecture. Too often, the concept of sustainability is connected to quantitative building performance, without enough consideration of how people use and enjoy spaces and how their wellbeing is influenced by their environment. This paper introduces the report Bo-miljø or Living Environment, written by Danish environmental psychologist Ingrid Gehl in 1971, into the current social sustainability discourse in architectural design as a way of gaining perspective into psychological wellbeing. The report is particularly relevant for considering the human dimension in housing design and identifies eight basic psychological needs that people have in relation to their living environments. The analysis of this report, and the synthesis of the findings with newer studies and definitions of social sustainability offer a framework for rethinking social sustainability. This essay analyses the findings from Gehl's report and contextualises it within current interdisciplinary research in this area. Critically analysing leading definitions and concepts in social sustainability and wellbeing, this essay offers an architectural perspective on design for social sustainability and wellbeing.