The Indonesian government has been struggling to improve the quality of teachers in its public and private schools. Several programmes of teacher education and teacher certification have been designed to enhance teacher quality. However, the programmes do not yet develop effective teachers. Supporting the government programmes, the Tanoto Foundation has facilitated teacher professional development programme since 2010, specifically in elementary schools in the provinces of Riau, Jambi, and North Sumatra. This paper first describes how the Tanoto Foundation has designed and implemented its teacher quality improvement programme for in-service teachers in remote schools in Indonesia and then uses this context to examine to what extent teachers benefited from these programmes. Reported findings broaden our understanding of how teachers can improve their quality via privately sponsored programmes.