Mucocoeles of the paranasal sinuses are relatively uncommon and in the past have been generally treated by an external surgical approach. Forty-eight mucocoeles in the frontal, fronto-ethmoidal and sphenoidal sinuses have been treated during the last five years, 20 by an entirely endonasal endoscopic approach and 28 by a combination of an external procedure and an endoscopic approach. There were no recurrences in the endoscopic group, with a mean follow-up of 34 months whilst three recurrences occurred in the combined external and endoscopic group which had a mean follow-up of 44 months. This may reflect the complexity and severity of concomitant disease. If a wide marsupialization can be achieved by an entirely endoscopic approach there are a number of advantages, notably a lack of facial scarring in children and young adults.