Purpose: This study examines the relationship between parental interaction style (responsive vs directive) and child-initiated joint engagement within caregiver-child interactions with toddlers diagnosed with autism spectrum disorders. Method: Videotaped interactions of 85 toddler-caregiver dyads were coded for child engagement and both parental responsiveness and directiveness. Results: Altogether, children spent less than one-third of the interaction jointly engaged. After controlling for child characteristics, parental style was associated with the initiator (child or parent) of joint engagement. Specifically, responsiveness predicted total time in child-initiated joint engagement, while directiveness predicted total time in parent-initiated joint engagement. Children's social behaviours were associated with child-initiated joint engagement. Discussion: Social initiations are a key target for children with autism spectrum disorders. Results demonstrate that child initiations and global social behaviour ratings are associated with parental responsivity. Responsivity may be a critical factor to facilitate children's initiations.