Acne is a chronic disease that is especially common among adolescents. It can have a considerable psychological and social impact that is not always correlated with clinical severity. The aim of this paper was to evaluate clinical severity and alteration of quality of life in acne patients, and to investigate a possible correlation between the two. A total of 82 patients with juvenile acne were included in this study. The clinical severity of acne was evaluated using the Echelle de Cotation des Lésions d'Acné (ECLA) scale. The Cardiff Acne Disability Index (CADI) was used to assess acne-related quality of life. Acne was mild to moderate in 61% of patients (ECLA < or = 12). A considerable alteration of quality of life was present in 51% of cases. There was a positive correlation between overall scores on the ECLA and CADI scales (P = .012) before and after treatment. Additionally, CADI score improved after effective treatment of acne. Acne may have an important impact on teenagers' psychological and social life. An objective assessment of this impact seems to be necessary. ECLA and CADI scores appear to be objective and simple instruments that may be used in acne management.