Three treatments for chronic pilonidal disease were compared in a randomized trial. Healing without formation of new sinuses occurred equally frequent after excision (E), excision with suture (E + S) and excision with suture under cover with clindamycin (E + S + C). The times of healing were significantly shorter after E + S (median 14 days, n = 29) than after E (64 days, n = 29) and tended to be even shorter after E + S + C (11 days, n = 30). Recurrence rates within 3 years amounted to 13 per cent after E, 25 per cent after E + S and 19 per cent after E + S + C, but the total time of healing after initial surgery as well as excision of recurrences was significantly shorter after E + S than after E and tended to be even shorter after E + S + C.