Extensive functional endoscopic sinus surgery (FESS) was assessed retrospectively from the viewpoint of out-patients on the basis of their responses to a postal questionnaire, particularly in the Tokyo metropolitan area. Seventeen patients were included in this study (six females and11 males) with an age range of 22–70 years. All the patients had at least ethmoid sinusitis. Additionally, some patients had maxillary or sphenoid sinusitis or polyps obstructing the nasal cavities. The average operation time and blood loss were 36 minutes and 31 ml, respectively. Four patients had to travel more than one hour to reach home. All of them used the train for travelling to and from the hospital. ’Doctors’ advice’ was the most common reason for the decision to undergo this ambulatory surgery. Nine (53 per cent) had some unexpected problems post-operatively. The establishment of a care pathway may improve the outcome of extensive FESS on an out-patient basis.