Policy and programming for preventing or countering violent extremism (P/CVE) in South-East Asian states are arguably underpinned by assumptions about the scale, nature and sources of risk of violent extremism. This paper assesses the accuracy and utility of influential assumptions and narratives about violent extremism in the context of South-East Asia, its extremist groups and movements, and the ways that radicalization has historically occurred in the region. P/CVE policies need to be examined in the context of empirical evidence and evolving local political contexts if they are to avoid worsening the situation. A holistic research agenda would help identify overlooked sources of risk and better adjust resource allocation in P/CVE programming.