Various models of specialized foster care have been developed, but research on them is limited. This longitudinal, exploratory study analysed data on adaptive functioning, emotional and social problems and self-concept in a specialized foster care service in Sweden. The focus of the study was on the development of the children and young people in placement. The Adaptive Behaviour Assessment System (ABAS-II) was used to measure adaptive functioning, and the Beck Youth Inventories of Emotional and Social Impairment (BYI) was used to measure self-rated emotional and social problems and self-concept. Self-ratings showed significant improvements in disruptive behaviour, anger, anxiety and depression. Adaptive functioning as rated by foster parents improved but not enough to catch up with the non-clinical norm group. The average adaptive functioning among the participants at baseline was considerably below the Swedish norm group. Similar to the results of a previous study of the same treatment model, children and young people rated improvement while their foster parents did not do so to the same extent. Possible explanations for this are discussed in the paper. The study is limited by the lack of a control group and by data attrition.