A pilot intervention that emphasized training and technical assistance to promote warm, sensitive, and responsive one-on-one caregiver-child interactions primarily during feeding and bathing/changing was implemented using regular staff in a depressed orphanage for children birth to approximately 8 years of age in Latin America. Despite a variety of unanticipated irregularities in the implementation of the intervention, many beyond the researchers' control, ward environments improved; caregivers displayed more warm, sensitive, and responsive interactions with children; and children improved an average of 13.5 developmental quotient (DQ) points after 4+ months' exposure to the completed intervention. Furthermore, 82% of the children had DQs greater than 70 before the intervention, but only 27.8% did so afterward. Although the training for all caregivers was aimed at children birth to 3 years, the number of different caregivers was reduced, and technical assistance was provided only to caregivers serving children less than 3 years, younger and older children (3-8 years) improved approximately the same amount. However, children who were transitioned from a younger to an older ward during the intervention improved less than did children who remained in either a younger or an older ward, the first evidence suggesting that the common orphanage practice of periodically graduating children from one homogeneous age group to another may impede their development. The study is consistent with others that have shown that orphanages can be changed, and increases primarily in warm, sensitive, responsive caregiver-child interactions can produce improvements in children's development.