In the period between May 1975 and 1976, 196 operations were carried out with an approach via the pterygomaxillary fossa, the majority for neurectomy of the vidian nerve in cases of vasomotor rhinitis or ethmoid polyposis. Other cases included neurectomy of the nerve of Bock in cases of obstructive tubaritis. The ease, precision and minimal operative trauma of this approach in comparison with the transmaxillary was the motive which led to an increase in our indications for surgery of the pterygomaxillary fossa. The experience acquired has led to the development of a routine procedure. This routine method is limited in the sense that note must be taken of a surgical field which is too narrow to work blind. It involves three risks: uncontrollable bleeding, functional failure if the nerve is not sectioned and possible ophthalmological complications.