Events in recent years have drawn considerable attention to the growing importance of transnational Muslim networks in the political and conflict dynamics of South and Southeast Asia. While much analysis has focused on militant groups, such as radical Islamist groups, broad-based ideologies, and even predominantly quietist networks also exert significant social and political influence. This report represents the culmination of a year-long initiative launched by NBR to explore the landscape of transnational Islam in South and Southeast Asia and assess its implications for these regions’ sociopolitical futures. NBR assembled an international team of experts to assess transnational Islam as it manifests in Bangladesh, Pakistan, India, Indonesia, Malaysia, the Philippines, and Thailand.