The paper seeks to understand how social dialogue can emerge in an anti-union context. Building from an institutional work perspective, we investigate how Dole in Costa Rica went from resisting to accepting social dialogue with two pineapple unions. The findings show that social dialogue is the result of a combination of convening, enabling, empowering and monitoring work involving a triadic relationship between supplier, international buyer and unions. Four stages were identified during which actors learned to collaborate and power relations were transformed. The paper highlights the importance of the dynamic nature of the triadic relationship in influencing social dialogue in a global value chain where production is located in an anti-union environment. The findings provide unique evidence on the role of the international buyer in supporting social dialogue as convener, facilitator, mediator and advisor. Acknowledgement :