Maintaining the quality and comparability of qualifications has become a major priority for vocational education and training (VET) systems world-wide, especially for those countries which have decentralised assessment and reporting systems. In the absence of external examinations, one policy solution to align the assessment standards of different providers is the introduction of assessment moderation. Yet there has been little, if any, research conducted in VET that has examined different approaches to moderation for quality control purposes. By drawing on lessons learnt in a range of settings (i.e. schools, vocational and higher education), this paper identifies the optimal conditions for undertaking social, external and statistical moderation approaches to quality control. It also identifies a range of potential system level factors that could hinder implementation within the context of the Australian VET sector.