Two longitudinal studies are reported examining the effects of full-time day care in Mapuche and non-Mapuche families in Chile. First, the Magellan-Leiden Childcare Study (MLCS) used a sample of 95 mothers with children younger than 1 year old (n = 36 in day care). Second, we partially cross-validated our results in a large and representative sample of 10,723 mothers and their children from the Chilean Encuesta Longitudinal de la Primera Infancia (Early Childhood Longitudinal Survey). In both studies, the quality of care for children provided at home was measured with the Home Observation for Measurement of the Environment. In the MLCS study, additional indicators of the mother-child relationship were measured. Day care was not negatively associated with the mother-child relationship and maternal sensitivity, compared to maternal care, or with the quality of the home environment. Positive changes in attachment security were found in Mapuche children who attended day care centers. Practice or Policy: We were able to confirm that type of care was not differentially associated with quality of the home environment. (author abstract)