The pattern of growth and development in the edible yam, Dioscorea rotundata Poir. (cv. "alafu"), was studied between May and October for three successive years by the method of growth analysis. Changes In dry weight with time of the various organs showed a well-marked correlation between them such that the sink which receives materials from the source, whether this be the mother tuber or the leaves, becomes the major sink at different times. At about the 8th week, when the new plant ceased to depend on the mother tuber and became autotrophic, both the relative growth rate and the net assimilation rate showed a marked change from high values to constant levels of 0.224 g g-1 wk-1 and 40 p m-2 wk-1, respectively, characteristic of the new plant. The mean value of the leaf area ratio was 72.5cm2 g-1. The implication of these studies for cultural practices is discussed and attention drawn to problems requiring further investigation.