The purpose of this article Was to examine the scientific evidence provided by single-subject design studies that supported effective intervention and educational practices for young children With autism. A revieW of the literature from 1990 to 2002 revealed 37 studies that meet the inclusion criteria. Research studies primarily employed multiple-baseline experimental designs and provided strong evidence for effectiveness through multiple replications of treatment effects. Practices supported by this research Were classified into three groups. Practices With Well-established evidence of effectiveness Were adult-directed teaching and differential reinforcement. Emerging and effective practices included peer-mediated interventions, visual supports, self-monitoring, and family member involvement in the intervention. Practices that Were probably efficacious included positive behavior support, videotaped model, and children's choices and/or preferences incorporated in learning tasks. For many of these practices, additional evidence may be provided by group design studies and single-subject design studies in Which older children With autism Were participants. © 2003, Sage Publications. All rights reserved.