Public procurement is a process whereby the public sector buys from private suppliers the goods, services and works it needs to accomplish its functions. It aims to obtain the best ‘value for money’, ‘in a timely, economical and efficient manner’.1 This traditional procurement’s goal was re-defined by scholars and policymakers to give space to non-economic objectives through the so-called sustainable public procurement (SPP).2 SPP pursues economic, environmental and social objectives within the purchasing process.3 Therefore, ‘social’ is one of the three dimensions that makes sustainability possible, and human rights are the backbone of social sustainability.