Sustainability standards and certification serve to differentiate and provide market recognition to goods produced in accordance with social and environmental good practices, typically including practices to protect biodiversity. Such standards have seen rapid growth, including in tropical agricultural commodities such as cocoa, coffee, palm oil, soybeans, and tea. Given the role of sustainability standards in influencing land use in hotspots of biodiversity, deforestation, and agricultural intensification, much could be gained from efforts to evaluate and increase the conservation payoff of these schemes. To this end, we devised a systematic approach for monitoring and evaluating the conservation impacts of agricultural sustainability standards and for using the resulting evidence to improve the effectiveness of such standards over time. The approach is oriented around a set of hypotheses and corresponding research questions about how sustainability standards are predicted to deliver conservation benefits. These questions are addressed through data from multiple sources, including basic common information from certification audits; field monitoring of environmental outcomes at a sample of certified sites; and rigorous impact assessment research based on experimental or quasi-experimental methods. Integration of these sources can generate time-series data that are comparable across sites and regions and provide detailed portraits of the effects of sustainability standards. To implement this approach, we propose new collaborations between the conservation research community and the sustainability standards community to develop common indicators and monitoring protocols, foster data sharing and synthesis, and link research and practice more effectively. As the role of sustainability standards in tropical land-use governance continues to evolve, robust evidence on the factors contributing to effectiveness can help to ensure that such standards are designed and implemented to maximize benefits for biodiversity conservation.

SignificanceVoluntary sustainability standards (VSS) may be an effective way to reduce the negative impacts of agriculture at regional to global scales. Here, we present an approach that highlights the potential of VSS to reduce some of the negative externalities associated with agriculture production. To illustrate this potential, we show that VSS could reduce the global environmental impacts from growing sugarcane. Further, most of this environmental benefit comes from targeting just 10% of production area. To realize these environmental gains, incentives for VSS adoption need to be sufficient to cover the costs of criteria compliance. Determining these costs and public and private-sector mechanisms for efficiently transferring VSS-adoption subsidies to farmers and millers are key future research needs.