To what extent is international trade free and fair? Because policy barriers to trade are often opaque and take on many forms, it is dicult to answer this question while relying on data on observable trade barriers. Here, I propose and implement a structural approach to estimating the magnitude of policy barriers to trade, measured at the trade partner level. The method allows for the possibility that these barriers are both asymmetric and discriminatory, aecting certain trade partners disproportionately. The approach reveals substantial latent policy barriers to trade, many times larger than observed taris. It also implies substantial eective policy discrimination, with exporters in subset of favored countries enjoying far superior market access conditions than their peers in unfavored countries. Combined, these results suggest that the existing world trading system remains far from a free and fair ideal.