Frontal sinus tumor-like lesions and benign neoplasms of surgical interest are, essentially, represented by mucoceles, pyoceles, inverted papillomas, osteomas and fibro-osseous processes of heterogeneous nature. in order to present our experience in dealing with expansive benign processes of the frontal sinus; we reviewed our series of 35 patients, operated on from January 1990 to July 1996. Surgical approaches were endonasal in 11, external in 18 and combined in 6 cases. The aim of the procedures was the removal of disease with restoration of the normal passages of ventilation and drainage, whenever possible, or, if necessary, obliteration of the sinus. The philosophy which led us to choose a surgical procedure rather than another, in each case treated, and the results achieved are discussed.