Are emerging markets undermining private environmental governance? In the past, most trade in agricultural commodities occurred between developed and developing countries, but in recent years the volume of South-South trade has increased significantly. The booming demand from emerging markets for food, feed, and fiber is now a key driver behind agricultural expansion, causing large-scale deforestation and biodiversity loss in the tropics. By examining the case of palm oil, this article argues that existing private governance institutions are not well equipped to deal with this crisis. They continue to operate on the basis of a North-South trade model, trying to leverage the market power of big-brand companies to achieve their sustainability goals. However, the effectiveness of this mechanism is increasingly undermined by the rise of South-South trade and the different structure and institutional context of emerging market value chains.