This presentation outlines the concept of market access as the core of WTO law, highlighting how trade liberalisation efforts have shifted from tariffs to more complex non-tariff barriers. It explains key tools like tariff schedules, quantitative restrictions, and import licensing, and shows how rules under GATT and WTO agreements regulate both duties and behind-the-border measures. It emphasises that while tariffs remain relevant, modern trade obstacles often stem from technical standards, health regulations, and opaque procedures, making international trade more regulated than truly free.