This paper presents promising methodologies for modeling and quantifying non-tariff barriers (NTB) to trade in the agricultural and food sectors. We limit the analysis to sanitary, phytosanitary, and technical regulations that can have an impact on trade and to methods that provide some quantitative estimates of the impact of such barriers on market equilibrium, trade flows, economic efficiency, and welfare. Given the heterogeneous nature of these regulations, a unifying methodology does not exist. Quantification of the effects of such measures has focused on a particular product and has relied on methods that belong to different fields of the economic literature. We provide a concise description and evaluation of the various methods available for a more comprehensive assessment of the impact of NTBs on trade and welfare. We conclude by identifying promising areas for future applied research.