This study examined the hypothesis that increases in the physical attractiveness of adolescent females brought about through orthodontic treatment would result in increased interpersonal attraction toward them by others. Subjects rated pictures of girls before and after they had undergone orthodontic treatment and also pictures of a control group of untreated girls matched to the experimental group for age and initial level of physical attractiveness. The results supported the hypothesis. Although pre- and post-control stimuli were not rated significantly differently, the experimental stimuli were rated significantly more positively posttreatment than pretreatment. These findings extend the results of previous research on physical attractiveness and interpersonal attraction to changes in the same person, utilize naturally occurring changes in attractiveness, and demonstrate that orthodontic treatment can have psychological as well as physical benefits for those who receive it.