This chapter describes Naturalistic Developmental Behavioral Interventions (NDBI), which are a scientifically validated set of approaches for children with autism. These interventions are derived from the fields of applied behavior analysis and developmental psychology, reflecting the essential combined contributions of these two disciplines. The intervention umbrella term, NDBI, was coined in Schreibman et al. (J Autism Dev Disord 45:2411–2428, 2015) to improve parsimony in the field and characterize a class of evidence-based interventions sharing many common features. This chapter provides an overview of the historical background of NDBI, as well as the core concepts and elements comprising these approaches. It concludes with a discussion of recent research and future directions relevant to NDBI.