The paper looks at how trade within ASEAN countries has changed due to the ASEAN Free Trade Agreement (AFTA). They used a method called the gravity model to study the impact of removing tariffs on trade between these countries. Their findings show that getting rid of tariffs helped increase trade for many different products. When it comes to imports, reducing tariffs had a bigger effect than on exports. The original ASEAN members benefited more from increased trade compared to new members. The research suggests that AFTA is doing a good job of boosting trade within ASEAN but that there's even more potential if they work on simplifying customs procedures and agreeing on product standards.