We conduct a meta-analysis of studies estimating price premiums for agricultural products differentiated by Geographical Indication (GI). Models accounting for differences across product characteristics (food categories) and institutions (PDO, PGI, trademarks) explain a large portion of the variance in estimated premiums. Specifically, GIs capture the highest percentage premium in markets for products with short supply chains and relatively low added value (e.g., agricultural commodities). The premium is lower for wine and olive oil, where alternative means of product differentiation (e.g., branding) exist. Controlling for product characteristics, GIs adopting stricter regulations (PDO) yield larger premiums than less regulated ones (PGI).