We investigate the factors that influence adoption of competition law using a panel of countries from 1970 to 2015. We find that in addition to development level, trading arrangements and peer pressure have also influenced adoption. The spread of competition laws adopted from Western precedents left a question regarding the extent they have been tailored to the diverse circumstances of the Association of Southeast Asian Nations countries. We document the nature, structure, conduct and scope of competition laws by comparing and contrasting the experience of the Philippines and Thailand. Our descriptive analysis reveals that the force and influence of the law are not entirely dependent on early adoption.