To identify any differences in emotional/personality development of a group of infants reared at home and a matched groups of infants enrolled in a day care center, data were obtained on behaviors of two groups of infants. The sample consisted of 15 demographically matched pairs of infants, ages 3-24 months at entrance. Data were collected through observation, questionnaires, administration of the Bayley Scales of Infant Development, and monthly telephone interviews with mothers. Five measures of emotional and personality development were used to assess the two groups: reaction to stranger, patterning, separation from mother, exploratory behavior, and eating and sleeping patterns. No significant differences were found between the Home and Center groups. However, since day care services are growing rapidly, it is clear that more research is needed to: (1) understand the complexity of the acquisition of attachment, which is crucial to development; (2) analyze the components of contingent responding; and (3) provide more detailed and definitive analyses of care-giving situations so the results may be incorporated in training techniques. (JF)