Because many children in Bermuda receive substitute care while their mothers work, several comparative studies were made of effects of maternal and nonmaternal care on children's development. Findings of an initial investigation indicated that 2-year-old children who had been in group-center care differed unfavorably from children in other forms of care on several measures. Subsequent analyses of data from children in out-of-home care before age 2 also revealed adverse effects of early group care. Particularly for males in care during their second year, care situations consisting of many hours per week in large groups with many children per caretaker were associated with lower intelligence, poorer verbal skills, and shorter attention than exhibited by children receiving other types of care. Additional studies provided support for the hypothesis that qualities of the day care environment affect the developmental levels of children's language and social development. Investigations of the long-term outcomes of group care indicated that no significant negative effects of infant group care existed in children 4 years of age; however, 4-year-old children in care at sitters' homes from 2 to 4 years of age appeared less intelligent, more passive, and more introverted than children in home care. Nonetheless, at 8 years of age, children who had experienced sitter care were found to be superior in math to children who had experienced infant group care and infant maternal care. (RH)