**Abstract**

Scientific literature suggests the neurobiological value of early intervention for children at risk of ASD and of other neurodevelopmental disorders, because it is based on the promotion of brain plasticity mechanisms in an ecological, noninvasive, and evidence-based way. Moreover, several authors suggest the greatest efficacy of early rehabilitation programs, involving both the parents and the children, is to improve not only sensory-motor and cognitive outcomes but also child-parent interactions and the wellness of the familiar system. In this chapter, the neurobiological fundaments and features for the early intervention and the most recent early approaches for children at risk of ASD (behavioral, developmental, naturalistic developmental behavioral, and parent-mediated interventions) will be explained.

**Keywords:** autism spectrum disorder, early intervention, behavioral interventions, developmental interventions, naturalistic developmental behavioral interventions, parent-mediated interventions
