There is a long history of Hmong migrations from the north to south. Most recently, Hmong have begun emerging in the southern-most parts of Laos, including Champasak and Attapeu Provinces, places where they never lived before, and some Hmong have tried to move south from Bolikhamxay to Khammouane Province. Southern Laos would appear to represent a new southern 'frontier' for the Hmong. This article looks at the interactions between the Hmong who have attempted to migrate into southern Laos and the Lao and Mon-Khmer language-speaking peoples they have encountered. Some Hmong movements into southern Laos have been accepted, while others have not. Crucially, negative racialized stereotypes about the Hmong being aligned with anti-government resistance groups, and being inherently destructive of the environmentas unfair as they may be have influenced the prejudiced responses in southern Laos to the arrival of the Hmong. Others simply see the Hmong as being difficult to get along with and administer (still another unfair stereotype). The cultural practices and habits of some Hmong arrivals have confused and upset some Mon Khmer language-speaking peoples in southern Laos. The movement of the Hmong from the north to the south, and the reactions of others to them, are important for understanding the ways Hmong are geographically positioning themselves, and how others are attempting to construct spaces and associated boundaries designed to restrict them. Thus, the focus of this article is on the reactions of others to the Hmong, and the way particular racialized boundaries have been developed.