The population structure of 5 endemic palms in the Vallee de Mai, on Praslin Island in the Seychelles Group, was investigated and reproductive activity recorded. Lodoicea and Phoenicophorium occurred throughout the entire valley. Verschaffeltia was only found on the valley floors, Deckenia and Nephrosperma mainly on the slopes. Mortality in the populations of the commoner species occurred in 2 unrelated stages, juvenile and senile. Estimates of the age of individuals of different sizes were made from the three most common species. Lodoicea is confirmed as the longest lived, though only reaching a maximum age of 200-350 yr; female plants die younger than males. Deckenia may reach 180 yr, Phoenicophorium 80 yr. The significance of the results is discussed and some questions posed for future investigation.