Regional trade systems and foreign direct investment impact economic growth in ASEAN countries. A study looked at Malaysia, Singapore, Thailand, Indonesia, and the Philippines from 1976 to 2002. Multilateral trade systems lead to faster growth than regional ones. Most measures of multilateral systems are positive and significant. Regional systems have mixed effects on growth, with some measures showing negative impacts. Foreign direct investment has a stronger effect on growth when countries are more open to liberalization. This suggests that regional trade groups can help boost economic growth in ASEAN nations.