The present study reports the results of surgical treatment of 175 consecutive chronic pilonidalis sinus cases by excision alone, excision and primary closure, excision and Dufourmentel's flap technique. The analysis of hospital stay , average recovery time, patient compliance and percentages of failures and recurrences enables us to state that Dufourmentel's technique is the best choice, allowing fast recovery with minimal discomfort and lower rate of recurrence. Moreover the good compliance of the technique and the use of recently introduced more effective local anaesthetics have allowed us to plan the treatment in a day-surgery setting with good clinical results.