Assurance schemes (certifications and labels) are widespread in the agri-food sector. This paper reviews the landscape of existing schemes, and the evidence on whether labels change consumer behaviour, and whether assurance schemes achieve positive change on the farm. The impact of existing labels on shopping behaviours appears limited: even for well-established schemes, market shares remain low, as factors such as taste, health, or price appear to dominate consumer decisions. Regarding farm-level effects, not all crops, standards, and geographies have been equally well studied, and many studies find no effect; but when an effect is found, it is usually positive. The paper identifies actions to improve the effectiveness and inclusiveness of existing and new assurance schemes, and also highlights the new trend of labels which communicate environmental impacts, rather than conformity with process or production requirements.