This directory is intended to:

contribute to the informed use of tree germplasm, which is an essential component of sustainable forestry and agroforestry practices, and promote wider use of quality germplasm.

Quality has both a genetic and a physiological component, and both are described in the directory. Quality descriptors can be used as criteria to select suppliers, and this will ensure that both the users and the suppliers recognize seed quality requirements. The directory also highlights the importance of biosafety issues, and it presents biosafety information that suppliers have provided

Although the directory focuses on tree taxa of importance in the tropics, it lists temperate taxa as well. It does not discriminate between taxa used for agroforestry and forestry. The purpose is to ensure that the information is useful to a wide range of users.