Vietnam’s successful tree-planting program seems to be slowing the transition from wood to cleaner, healthier cooking fuels such as liquified natural gas. Rural families apparently find it difficult to switch to a cleaner cooking fuel because supplies of wood are plentiful while the poor development of roads and markets means that natural gas is simply not available. Vietnam's experience suggests that when governments encourage farmers to plant trees they should consider reducing the possibility of negative health effects by making investments in rural infrastructure at the same time.