OBJECTIVE: To objectively evaluate the nasal function in adults operated on for unilateral cleft lip and palate with one-stage or two-stage palate closure. DESIGN: The population consists of all unilateral cleft lip and palate patients born from 1960 to 1987 and treated at the Cleft Lip and Palate Center, Uppsala University Hospital, Sweden. The patients were treated according to the same protocol except for palate closure, which was performed in one stage until 1977 and in two stages thereafter. Eighty-three patients participated. Mean follow-up time after primary surgery was 32 years. An age-matched control group underwent the same examinations. MAIN OUTCOME MEASURES: Nasal minimum cross-sectional area (cm(2)) and volume (cm(3)) were assessed (acoustic rhinometry). Airflow resistance (Pa s/cm(3)) (rhinomanometry), peak inspiratory flow (L/min) (peak nasal inspiratory flow), and number of identified odors (Scandinavian Odor Identification Test) were determined. RESULTS: The cleft side of unilateral cleft lip and palate patients had significantly lower values for all parameters compared with controls (p