Tackling social and environmental issues resulting from agricultural expansion in Southeast Asia has been a longstanding focus in the literature. Yet unlike other cash crops such as coffee, palm oil, or cocoa, rubber has received very little attention from academics and policymakers alike. The late 2000s saw a mass rubber-driven clear-cutting of some of the world’s most biodiverse forests, especially in Southeast Asia where over 90% of the world’s natural rubber supply is currently being produced. Since this rubber boom, and in response to increasing scrutiny from watchdog groups, many actors including states, NGOs, civil society, as well as agribusinesses have intensified efforts to develop and implement sustainable rubber initiatives. Focusing on sustainability governance for whom, by whom, and for what, I examine emerging trends in who holds the decision-making power to influence changes in the (sustainable) production of rubber in Vietnam. As a critical upstream node in the global rubber supply chain, Vietnam offers a unique analytical perspective from a political ecology approach. Multiple governance schemes are simultaneously in effect here, including top-down due diligence regulations such as the European Union Deforestation Regulation, voluntary sustainability standards, as well as bottom-up homegrown sustainability guidelines co-developed by agribusinesses and local NGOs. How these sustainability guidelines and regulations align or come into conflict with one another is a central question that my research addresses. Intended or not, these governance initiatives – and the sustainability discourses they draw on – often blame or exclude Global South producers, framing them as practicing backward and unsustainable agriculture. Through semi-structured interviews and document analysis, I find a strong risk of small-scale agribusinesses being marginalized in the Vietnamese rubber sector, as the sustainability movement increasingly favors a more regulated, legible, and traceable supply chain.