Southeast Asia is critical for broad studies of human evolution because the region yields one of the highest diversities of Pleistocene hominin species. Although evolutionary trends and biogeographic affinities among Southeast Asian hominins have long been studied over the past decades, the growing fossil records from the region have complicated what was once a straightforward evolutionary story. Integrating multiple lines of evidence (faunal, chronological, genetic, and environmental information) challenges the traditional hypothesis of Pleistocene hominin and faunal dispersal patterns in Southeast Asia, and the timing and ecological influences on their settlement success. In particular, questions of how early hominins adapted to their surrounding environments and exploited available resources in the region, and how they dispersed into island Southeast Asia, remain hotly debated. The aim of this workshop was to bring together experts to examine the environmental conditions, ecological factors, and types of corridors that allowed Pleistocene hominins to cross biogeographic barriers. This workshop improved our understanding of the potential routes and timing of early hominin expansions and opportunities for admixture. The final output of the discussion by workshop participants will result in the evaluation of large-scale ecological and biogeographical schemes for the dispersal of Pleistocene hominins across Southeast Asia.