Infants develop attachment to their caregivers very early on. The quality of attachment is considered to be crucial for the emotional development of humans and animals alike. Despite its importance, very little is known about how attachment develops between children with Autism Spectrum Disorder (ASD) and their caregivers. The purpose of the present study was to assess the attachment patterns of two young children with ASD with their parents and to identify the means for promoting parent, child, and parent-child relational characteristics that may contribute to the development of secure attachment. The results replicated prior findings pertaining to attachment quality of children with ASD and demonstrated the effectiveness of a naturalistic, behavior-analytic intervention in improving the quality of their attachment.