The analysis and intervention of communication is an important focus of autism research. The present study is a microanalysis of the communicative behaviour of 10 autistic children with their parents and a therapist. Protests, appropriate initiation and responses of the children were analysed in relation to demands and the specific feedback of the adults. After 20 months of structured therapy changes in the communicative behaviour of the participants were demonstrated. Autistic children showed different communicative pattern with their parents compared to a therapist. The non-verbal group exhibited significantly more protests and decreased responsivity with their parents compared to the therapist. The verbal group interacted with their parents predominantly by echolalia. After 20 months a significant reduction in protests, increased compliance and responsivity were obvious in the non-verbal group. The verbal group showed a reduction in echolalia as well as increased responsive and spontaneous communication. The results demonstrate that even non-verbal autistic children are sensitive towards different interaction partners. Over the observation period participants showed a reduction in behaviour problems and positive developments of communicative behaviour.