This chapter analyses the roles of principals in building teacher leadership capacity in the process of school turnarounds in the Lao People’s Democratic Republic (Lao PDR) or Laos. Qualitative interviews were conducted with 12 participants (principals and teachers), all of whom were selected by purposive sampling. The findings show that principals in the Lao context mostly delivered ideas and facilitated the development of teacher leadership capacity by exercising transactional and distributed leadership. In addition, principals and teachers recognised the importance of transformational leadership style, which meets the current needs of educational development in Lao PDR, which has increased contact with foreign nations, especially in the form of educational assistance that requires new vision. These findings may extend the knowledge of low-performing school transformation and assist in policy making for low-performing school transformation in developing countries that face similar situations to Laos.