In this issue of Transfusion Medicine Reviews, we are pleased to offer readers an assessment as of April 2020 of COVID-19 convalescent plasma (CCP) by H Cliff Sullivan and John Roback of Emory University in Atlanta. The authors have brought together in one document those relevant background studies which have been used as support for implementation of CCP in the pandemic [1]. Readers will note how few high-quality randomized trials actually exist. Although the absence of randomized controlled data is to be expected for rare and orphan diseases, there is no excuse for their absence in illnesses with thousands of patients. In fact, the sheer numbers of individuals afflicted with and dying from COVID-19 present a clear ethical as well as scientific requirement that the health care system seek truth regarding treatments. We all hope that CCP will be a beneficial treatment, and a preliminary report by Duan et al of its uncontrolled use in 10 patients in China might be seen as encouraging [2]. Although bypassing randomized controlled investigation of CCP may be tempting given the sense of urgency to “just do something,” a mistake repeated is a decision taken. Failure to “study first before wide-scale implementation” risks doing harm to both patients and the health care system. Consideration of the possible harms is important for research equipoise and informed consent and serves to remind us of the ultimate importance of good scientific method.