Nasal respiratory function and its relationship to growth development of the craniofacial structure has been a subject of interest and controversy for over 100 years. The otolaryngologist as the primary physician with responsibility of managing the upper respiratory tract is obviously most intimately involved with diagnosis and treatment of upper respiratory tract problems. To further evaluate the evidence regarding causes of craniofacial growth, a study was done involving pretreatment orthodontic subjects and their manifestation of classic signs of adenoid facies ("long-face syndrome"). Randomly selected were 106 subjects, ranging in age from 6 to 13 years, for evaluation of the facial features and medical history associated with long-face syndrome. No conclusive proof was found that nasal respiratory obstruction alters facial growth development. Studies of the nasal respiratory function need to be done utilizing clear definitions of respiratory mode and objective; reproducible techniques of measuring respiratory modes must be employed. Highly selected orthodontic patients can benefit from adenoidectomy and/or tonsillectomy.