Objective: The development of the Cleft Aesthetic Rating Scale, a simple and reliable photographic reference scale for the assessment of nasolabial appearance in complete unilateral cleft lip and palate patients. Design: A blind retrospective analysis of photographs of cleft lip and palate patients was performed with this new rating scale. Setting: VU Medical Center Amsterdam and the Academic Center for Dentistry of Amsterdam. Patients: Complete unilateral cleft lip and palate patients at the age of 6 years. Main Outcome Measures: Photographs that showed the highest interobserver agreement in earlier assessments were selected for the photographic reference scale. Rules were attached to the rating scale to provide a guideline for the assessment and improve interobserver reliability. Cropped photographs revealing only the nasolabial area were assessed by six observers using this new Cleft Aesthetic Rating Scale in two different sessions. Results: Photographs of 62 children (6 years of age, 44 boys and 18 girls) were assessed. The interobserver reliability for the nose and lip together was 0.62, obtained with the intraclass correlation coefficient. To measure the internal consistency, a Cronbach alpha of .91 was calculated. The estimated reliability for three observers was .84, obtained with the Spearman Brown formula. Conclusion: A new, easy to use, and reliable scoring system with a photographic reference scale is presented in this study.