Global supply chains power 80% of world trade, but also host widespread environmental, labor, and human rights abuses in developing countries. Most scholarship focuses on some form of sanction to motivate supply chain members, but we propose that the fundamental problem is not insufficient punishment, but a lack of trust. Fickle tastes, incessant demands for lower prices, and spot market indifference force suppliers into a constant struggle for economic survival. No trust can grow in such an environment, and few sustainability practices can take meaningful root. Responding to multiple calls for scholarship in the supply chain literature, we propose a trust-building process by which supply chains can evolve from indifference and hostility to a relational partnership that produces joint investments in sustainable practices. The result is a supply chain that is more efficient, more humane, and embeds sustainability in the supply chain for the long-term.