The aim of this study was to establish if there are any symptoms which can predict increased patient satisfaction following Endoscopic Sinus Surgery (ESS) and whether these symptoms correlate with Lund-Mackay score on Computerised Tomography (CT). A prospective observational study was performed. Ninety-three consecutive patients who were offered ESS were recruited from an otolaryngology department in a UK Teaching Hospital. All patients had failed medical therapies for chronic rhinosinusitis (CRS), recurrent acute sinusitis and/or nasal polyposis. Patients were asked to complete a questionnaire pre-operatively and 12months after surgery. Symptoms were assessed using a visual analogue scale. Endoscopic examination of the nose was performed pre and post-operatively. Lund-Mackay score was recorded for the pre-operative CT scan. Results were analysed using linear regression analysis and Pearson correlation coefficient. All symptoms improved after ESS (P<0.001). However, a high pre-operative score for nasal discharge and olfactory disturbance were predictive of lesser improvement in symptom scoring (P<0.001). Patients undergoing polypectomy with ESS demonstrated greater improvement in symptom score than those undergoing ESS with septoplasty or turbinate reduction surgery. There was no correlation between symptom score improvement and pre-operative Lund-Mackay score (r=0.09). Patients who have high pre-operative symptom scores for nasal discharge and olfactory disturbance may gain less benefit from ESS, whilst those with nasal polyposis appear to perceive the greatest benefit. Increasing pre-operative Lund-Mackay score is not a predictor of a favourable operative outcome.