The aim of this study is to examine whether the asymmetrical pattern of communication usually found between people who use augmentative and alternative communication and their partners using natural speech was also found in the interaction between non-vocal young preschool children with cerebral palsy and their parents. Three parent-child dyads (children's age 2;5-3;4 and developmental age 18 months) were video-recorded during everyday activities. Three comparison dyads with children matched for developmental age and sex with the children in the focus dyads were studied in the same situations. There were only small differences between the two sets of children, while the parents in the focus dyads were more active than the parents in the comparison dyads. The results are discussed in relation to early intervention, aiming at enhancing development of functional patterns of interaction. (Contains 7 tables.)