Studies are described on the in vitro multiplication of chestnut axillary buds from 3- month-old seedlings and 5-year-old trees grown in containers. In attempts to eliminate the autointoxication of expiants by tannins released into the culture medium, both the importance of dipping in sterile water before culture, and of the age and the bud position on the twig was established. Murashige and Skoog’s medium with BAP (1 mg 1_1) permitted the multiplication of juvenile as well as adult material. Lowering the pH to 4, with the Ca and Mg concentrations doubled, promoted multiplication and elongation. Whereas the multiplication medium permitted the elongation of leafy shoots taken from buds, it did not do so for buds originating from adult material. For the latter it was necessary to add auxin, adenine and activated charcoal to halt multiplication and allow elongation. Some roots were obtained, but only on the juvenile material.