To overcome the limitations of conventional biodiesel processing technology, researchers have investigated alternative production methods, one of these being supercritical methanol processing. It has been reported that this process can handle feed contaminants, has simple purification operations and achieves high conversion in short reaction times. Despite these promising results many factors have been shown to affect the level of conversion at the high temperatures and pressures required. The purpose of this review is to clarify the inter-relation between these parameters and evaluate the merit of supercritical methanol processing as an alternative to the conventional homogeneous alkaline catalysed method. (C) 2010 Elsevier Ltd. All rights reserved.