Planting trees to sequester carbon dioxide mitigates climate change, but it has been contended that insufficient attention is given to the quality of the germplasm established in afforestation/reforestation programmes, limiting sequestration opportunities. To understand current practices in the choice, sourcing and delivery of tree planting material, we undertook a desk review of 38 Clean Development Mechanism (CDM) afforestation/reforestation project design documents (PDDs) from Africa, Asia and Latin America. Detailed examination indicated most PDDs identified for planting species that could be locally appropriate, with a large number of indigenous taxa as well as exotics chosen. The number of indigenous species in some designs appeared however to be unrealistic in terms of ensuring germplasm access. Reference to an online germplasm supplier database and comparison with the available literature supported the hypothesis that many PDDs pay insufficient attention to the choice, sourcing and delivery of planting material, which is likely to impact on the quality of the trees planted. Moving forward, it is clear that greater attention to available sources, more local testing of germplasm and working in closer relationship with local communities in nursery development are among the interventions required to support tree-based sequestration initiatives.