Following the identification of the invasive non-native species Didemnum vexillum, Kott 2002, on a Scottish shellfish aquaculture unit, a control method was needed to permit the legal movement of live Pacific oysters (Magallana gigas) off from the farm, and which would kill the pest species but result in acceptable mortality in the aquaculture species. Following a literature review, the most relevant control method in our case was determined to be a bath treatment. Twelve relevant published studies were found describing bath treatments for fouled shellfish, although some results were contradictory and their interpretation was complex. This report presents a review and analysis of the evidence needed to have a control method accepted for initial trial by the Scottish shellfish industry and by the relevant national regulatory authorities. The control method that will go forward for field trial is immersion in freshwater for a minimum of 24 hours. Associated data are presented for download.