Summary
Coming soon
This report examines what additional insights on the impact of voluntary sustainability standards (VSS) can be gained by expanding beyond the strict inclusion criteria typically used in systematic reviews and considering a broader range of evidence on smallholder economic, social, environmental, institutional, and behavioural outcomes. It uses Rainforest Alliance as a case study.
Drawing on the evidence base developed for the 2026 Evidensia systematic review ‘Effects of Voluntary Sustainability Standards on smallholder yields, price, costs and income in the agriculture sector: Insights from scientific evidence (2008-2024)‘ the authors identified 19 additional peer-reviewed studies on the Rainforest Alliance published between 2019-2024 vs. the systematic review’s 4.
Unlike the original review, which focused mainly on quantitative counterfactual impact evaluations, this study includes insights from papers with diverse methodologies, data sources, and study designs, allowing comparison between a narrowly defined evidence base and a wider body of qualitative, quantitative, mixed-methods, and experimental research.
The broader evidence base confirms that impacts on yields, prices, and incomes remain mixed and highly context-dependent, while more consistent benefits are found in areas such as knowledge and skills development, adoption of improved agricultural practices, market access and buyer relationships.
The study also highlights findings often missed by stricter impact evaluations, including the importance of certification costs, governance arrangements, behavioural responses, and the conditions that enable or constrain positive outcomes, showing that certification tends to influence practices and behaviours more consistently than final livelihood or environmental outcomes.
The authors recommend complementing rigorous impact evaluations with a wider range of research methods to better understand implementation processes, contextual factors, behavioural change and institutional dynamics.
They further recommend improving indicator standardisation, transparency, data collection, and long-term evidence generation, while strengthening support mechanisms such as training, producer organisations, financial assistance, and buyer engagement to enhance VSS effectiveness.