The Lao People's Democratic Republic (Lao PDR) is one of the most ethnically and linguistically diverse nations in Southeast Asia. The post-1975 government's policies regarding ethnic minority peoples are often considered to represent an ideological shift from earlier monocultural orientations to a discourse of interethnic equality and solidarity. Yet a deeper reading of official policies, combined with an examination of planning measures, reveals a persistent discourse of ethnic Lao centrality. This paper first examines the apparently contradictory official discourses on language, ethnic minorities and education in Laos, and how these discourses are reproduced, adapted or contested on the ground by teachers and students in ethnic minority classrooms. I first present a discourse analysis of selected policy documents, supported by interviews with key policy-makers followed by an analysis of teacher code choice in three ethnic minority classrooms together with data from teacher interviews. The paper is based on ethnographic fieldwork carried out in Nalae district, Luang Nam Tha Province and five years of experience working in education development in the Lao PDR. (Contains 6 notes.)