Randomised controlled trials (RCTs) are considered to be the gold standard in evaluating medical interventions; however, people from ethnic minorities are frequently under-represented in such studies. The present paper addresses a previously neglected debate about the tensions which inform clinical trial participation amongst people from ethnic minorities, in particular, South Asians, the largest ethnic minority group in the UK. In a narrative review of the available literature, based mainly on US studies, the present authors aim to make sense of the issues around under-representation by providing a theoretical reconciliation. In addition, they identify a number of potential barriers to ethnic minority participation in clinical trials. In so doing, the authors recognise that the recent history of eugenic racism, and more general views on clinical trials as a form of experimentation, means that clinical trial participation among people from ethnic minorities becomes more problematic. Lack of participation and the importance of representational sampling are also considered, and the authors argue that health professionals need to be better informed about the issues. The paper concludes by offering a number of strategies for improving ethnic minority accrual rates in clinical trials, together with priorities for future research.