Despite being minimally invasive, the endonasal approach to inflammatory frontal sinus disease may present problems. Previously, prevalent external frontal surgery and osteogenic inflammatory frontal sinus processes often involved difficult access to or stenosis of the frontal sinus outflow tract. We present 6 cases of intractable inflammatory frontal sinus disease and discuss surgical approaches. Subjects were 4 men and 2 women 27 to 74 years old. The 5 cases of recurrent frontal sinus disease required Draf type II drainage or an endoscopic modified Lothrop procedure (EMLP) with or without stenting. The 1 case of frequently recurring inflammatory fontal sinus lesions with a markedly ossified frontal sinus outflow tract required the obliteration of fatty tissue. None of our cases showed recurrence after a relatively short follow-up of less than 5 years. Despite the relatively small case number and short follow-up, our results suggest that recurrent and extensive inflammatory frontal sinus lesions require tailor-made treatment using both endoscopic and external approaches.