Autism and its related disorders are characterized by widespread abnormalities of social interactions and communication, as well as severely restricted interests and repetitive behaviours. These disorders are described as lying on a continuum of severity, referred to as the autism spectrum, reflecting the diversity of symptoms in children with autism. Studies indicate that one major commonality among children on the autism spectrum is an impairment in their understanding of other people's perspective or point of view. This ability is seen as the major underlying process in children's overall social functioning. Newly-developed theories of how children typically develop perspective taking have provided important insights for assisting children with autism to improve their social understanding. However, while intervention programs are aimed at improving children's social competence through increasing their ability to understand someone else's point of view, the underlying mechanisms and effects on children's ability to reason about other people's perspectives are not well researched. Theo Elfers is investigating how perspective-taking develops by focusing on a specific aspect of social cognition — the role of children's active engagement in perspective-taking tasks. Studying both children with and without autism, Elfers is giving the children structured tasks that allow the child to take both perspectives in a social exchange (e.g., gift giver and gift receiver), while allotting enough time for the child to remember each perspective and prompting the child to anticipate the other's perspective. Ultimately, this work should provide researchers and mental health professionals with insights into how perspective-taking develops, and also increase the effectiveness of future training programs aimed at fostering social competence in children on the autism spectrum.