This study aims to understand the predictors of adaptation among primary caregivers of children with a pervasive developmental disorder (PDD). PDD presents particular challenges for caregivers because of the communication and socialization challenges of affected children, as well as the uncertainty surrounding the cause, prognosis and recurrence risks. The literature suggests that these challenges may make the process of adapting to having a child with a PDD different than it is for other chronic conditions. This study of caregivers is based on Lazarus and Folkman s Transactional Model of Stress and Coping. A cross-sectional design will be used to investigate the relationships among causal attributions, control perceptions, coping and adaptation. Caregivers will be recruited from support groups, listservs and magazines targeted to autism and other PDDs. Participants will be asked to complete either a web-based or paper survey. The main outcome measure is psychological adaptation to caregiving a child with PDD.