Well baby clinic records on 1, 186 infants born in 1975 to 1976 on the island of Tutuila, American Samoa, form the basis for this study of the growth in weight and length from birth to 12 months. Semi-longitudinal curves of weight and length indicate that these infants have median weights near the NCHS 75th percentile (boys) and 90th percentile (girls) up to 6 months, falling to just below the 75th percentile by 12 months. Median lengths are between the NCHS 50th and 25th percentile. Weight gain from birth to six months was found to be higher than for any other reported population (4.92 kg, sexes combined). The infant feeding pattern was found to exert a significant influence on rate of weight gain for boys between birth and 1-4 months, with the breast-fed boys gaining more rapidly than artificial-fed infants.