Rules of origin (RoO) represent an important chapter of preferential trade agreements (PTAs). They aim at preventing the entry in the PTA of products originating from third countries through the partner that applies the lowest tariff, for being subsequently circulated in the entire PTA duty-free (a phenomenon known as ‘trade deflection’). However, also unilateral trade arrangements have their own RoO. The Generalized Systems of Preferences (GSPs) or the US AGOA programme for instance, are preferential trade arrangements adopted unilaterally by some industrialized countries to offer mark access (without reciprocity) to developing and less developed countries from selected countries. A new paper published by FERDI (Fondation pour les Études et Recherches sur le Développement International) shows that the adoption of more flexible product-specific rules of origin within preferential agreements would give a significant boost to global trade.