The EU public procurement law was developed to enhance the free movement of goods and the free provision of service. ‘Buying national’ was at the core of domestic procurement law and the directives were seen as a way to enforce non-discrimination among European economic operators. Environmental and more widely understood sustainability concerns came later and were for a long time looked upon with suspicion before being embraced in the last reform of EU public procurement law. Some institutions in the EU, and notably the Commission, are still concerned about the possible misuse of sustainability to reintroduce unlawful discrimination among economic operators. The 2014 rules on LCC must be read as an attempt to ‘square the circle’, allowing contracting authorities to take into account all aspects of the life-cycle of the goods or services purchased while ensuring the level playing field for all competitors. The new rules on LCC, however, demand much effort to become operational and pitfalls need to be mapped and properly understood.