Further fieldwork is a matter of particular urgency. As elsewhere among the world’s major language families, Tai-Kadai’s territory is home to speakers of endangered languages. Concern is great that children of those now speaking many Tai-Kadai varieties are substantially modifying and even abandoning their parents’ language. This volume documents varieties under threat, pointing to how important it is for more work of this kind to be undertaken while there is still time. Required will be well-trained linguistic researchers, motivated local speakers, appropriate institutional assistance and the acquiescence, if not active support, of governments and local officials. In the past two or three decades Tai-Kadai researchers have been fortunate in that policies of states in the region have generally moved in the direction of facilitating greater access to field sites; the profession’s thanks are due to individuals and official units involved in this movement. Gratitude is also due to the funding bodies which have supported Tai-Kadai research. It is hoped that work reported in this volume may encourage others to address these challenges, gain necessary support and pursue further field studies in this critical area.