A clinical study was carried out to determine if parental presence during dental treatment alters the child's behaviour when compared with parental absence. Thirty-two children who attended with a parent for a dental recall visit were randomly assigned to a parent present or a parent absent group. The age of the children ranged from 4 to 12 years. Twenty-three mothers and nine fathers attended during the study. Those parents absent during the visit viewed proceedings from behind a one-way mirror. Each visit was standardised in procedure and recorded on video tape. The results showed that 4 to 8-year-old children exhibited significantly more negative behaviour, regardless of parental presence, than the 9 to 12-year-olds. The presence of the parent did not lead to significantly greater negative behaviour. The parent's need to see what happened during the visit and the child's need to have a parent present were the most important reasons for having a parent present. Parents viewing from behind a one-way mirror were as satisfied with their position as parents who had been actually present in the surgery.