Life Tables to age twenty for Down's syndrome cases born in British Columbia from 1952 through 1971 were constructed using data from the British Columbia Health Surveillance Registry. No significant difference in survival to age twenty between males and females was found either in the presence or in the absence of congenital heart anomalies. Data from the life Tables show that Down's syndrome patients with congenital heart anomalies experience higher mortality to age twenty than cases without congenital heart anomalies.