There are growing concerns in the Thai construction and engineering sector as to how courts and tribunals will assess design defects and a project’s fitness for purpose, leading employers and contractors alike to question the extent of their design obligations. Many of these concerns arose following a surge of legal commentary on the impact of the UK Supreme Court’s 2017 judgment in MT Højgaard v E.ON (“MT Højgaard”). In short, the court decided that, in a contract obliging a contractor to work with reasonable skill and care and to produce an end-product which was fit for purpose,the fitness for purpose obligation took precedence where the two standards conflicted.