This review aims to explore the effects of placing children with special needs in inclusive educational settings, compared with segregated placement on measures of academic achievement and psychosocial adjustment. A secondary aim is to explore how different child or setting characteristics (gender, age, type and severity of special need, part- or full-time inclusive education, and co-teaching) might moderate outcomes. The effects of placing children with special needs in grades K-12 into inclusive educational settings are inconsistent. Findings from this review suggest that, in general, inclusion neither increases nor decreases learning and psychosocial adjustment of children with special needs in the OECD countries. [This summary is based on "The Effects of Inclusion on Academic Achievement, Socioemotional Development and Wellbeing of Children with Special Educational Needs" (EJ1358852).]