Naturalistic instructional approaches are used to provide intentional and systematic instruction to young children with disabilities during typically occurring activities. Several naturalistic instructional approaches have been described in the extant literature, although different terms have been used to refer to these approaches (e.g., activity-based intervention, embedded instruction). The purpose of this systematic review was to identify, examine, and summarize the empirical literature focused on naturalistic instructional approaches for preschool children with disabilities when instruction was delivered in classroom settings. Forty-three studies that met established inclusion criteria were reviewed and coded using systematic procedures. Studies were coded to permit within- and across-approach comparisons as well as with respect to quality indicators for study design features and relationships to reported outcomes. Findings suggest a need to specify clearly the contextual and procedural components of naturalistic instructional approaches to advance understanding about this evidence-based practice and the functional relationships between implementation of the approaches and child learning outcomes. (author abstract)