Technical barriers to trade (TBT) and sanitary and phytosanitary (SPS) measures make up the core of non-tariff measures (NTMs) both within the multilateral trade policy regime, administrated by the World Trade Organization (WTO), and within the preferential trade policy regime, represented by preferential trade agreements (PTAs). Technical barriers to trade and SPS provisions have been present in PTAs since the mid-1950s and have grown in importance since the WTO TBT and SPS Agreements entered into force in 1995. This chapter assesses TBT and SPS measures in selected PTAs and outlines likely trends. The first section focuses on the design and evolution of TBT and SPS measures present in three recent mega-regional PTAs: the United States–Mexico–Canada Agreement (USMCA), the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP), and the Regional Comprehensive Economic Partnership (RCEP). The second section examines likely trends in the development and application of TBT and SPS provisions in PTAs with the expectation that some of these provisions will eventually be multilateralised.