This study profiled various levels of engagement and related communication behaviours among 50 Asian Indian Tamil autistic children (AUT) and their mothers. The interaction was compared with two groups of mother-child dyads of non-autistic (NA) children, 50 in each group, matched for chronological age (CA), and for language level (LL). Results indicated that despite mother’s efforts to engage with their children, autistic children were often ‘engaged with objects’ or remained ‘unengaged’ due to children’s preference for solitary play, while NA children were often engaged in ‘co-ordinated’ and ‘people engagement’. Across the three groups, mothers predominantly took the lead and dominated the interaction, irrespective of children’s language levels. These initiations by the mothers were often to provide instructions and to ask ‘What’ questions. Autistic children initiated communication predominantly to ask for an object and responded often in the form of negations and protests with limited verbal output or non-verbally. Most of the communication behaviours of both children and mothers in AUT group was quantitatively and qualitatively different when compared to those in both the NA groups, indicating unique nature of interactions despite matching for CA or LL. The observations from the study highlights the need for considering adult’s contingent behaviours also, while assessing communication skills of autistic children in order to provide effective intervention.