Ready-made-garment (RMG) production for sale in the EU and USA is a key source of economic development for Bangladesh. The 2013 collapse of Rana Plaza revealed worker safety and other social issues in RMG factories in Bangladesh, showing that formal, top-down approaches to these problems, including corporate codes-of-conduct and reforms in Bangladeshi labor laws, have little effect. Supply chain sustainability is a key issue for business, government and civil society. Satisfactory theoretical approaches to promoting social sustainability in supply chains are lacking. A case study using qualitative document analysis identifies the key institutional factors related to social sustainability in the Bangladeshi RMG industry, with a modified version of the Institutional Analysis and Development (IAD) framework as an analytical frame. Key elements of other frameworks for social sustainability are discussed in terms of how well the IAD framework captures those concepts, and how employing the IAD could enhance supply chain analysis.