There are no adequate measures to assess health-related quality of life before and after surgical orthodontic treatment. This study aims to develop and evaluate a new self-administered questionnaire, which will ultimately be an evaluative index of surgical orthodontic treatment. Items for the questionnaire were chosen based on a variation of the Item Impact Method (Guyatt et al., 1987). Questions were selected from three previously validated oral health measures. Validity testing involved 95 participants. Test-retest reliability was assessed in a subgroup of this sample (n = 16). The discriminant properties of the questionnaire were tested using three cross-sectional groups: pretreatment, 2--6 months post-operative and more than 2 years post-operative groups. The questionnaire showed discriminant validity as many hypotheses concerning differences between groups in quality of life were supported. There were significant associations between questionnaire overall scores and the global rating of overall health (p < 0.000). The Cronbach alpha and intraclass correlation coefficient for the questionnaire were 0.95 and 0.96, respectively. These results suggest that this new questionnaire is valid and reliable.