A rapid multiplication technique of tannia (tanier, cocoyam, Xanthosoma sagittifolium) is suggested for developing countries, in particular, the Windward Islands of Dominica, St. Lucia, St. Vincent and Grenada, where Pythium root rot or tannia rapid yellowing disease (TRYD) caused by Pythium myriotylum. has been seriously affecting tannia production. The rapid clonal multiplication of disease-free plant material is done through a two-phase production system - a combination of in vitro propagation and subsequent in vivo mini-setting. The Murashige and Skoog (1962) basal medium was used for meristem initiation and then amended by omitting benzylamino-purine (BAP), but including 0.1 mg/1 1-naphthaleneacetic acid (NAA) for prolific calli formation and plant regeneration. The technique described can improve tannia germplasm stock and at the same time provides a system that is practical and economically affordable to developing countries.