Southeast Asia is integrating economically and all Association of Southeast Asian Countries (“ASEAN”) have agreed to introduce competition laws by 2015. Considerable differences in levels of economic development as well as legal and political institutions means that competition law integration is unlikely to follow the same path as in Europe. Considerable differences in existing and proposed competition laws reflect local circumstances. However, there are considerable similarities in the way business operates in the region. This chapter considers one important feature of the way business operates in Southeast Asia – the dominance of family-owned business groups and conglomerates that control substantial parts of all economies in Southeast Asia. Some implications for competition law are drawn.