Four hundred and eighty-one patients with an ovarian cyst considered to be benign on the basis of clinical and ultrasonographic findings underwent diagnostic laparoscopy. All malignant tumours (9 cases) were recognized by diagnostic laparoscopy and were treated immediately via laparotomy. When a cyst was identified as being benign on laparoscopy, the diagnosis was always confirmed by histological examination. Sixty one patients (64 cysts) were treated via laparotomy immediately after laparoscopy for the following reasons: malignant or suspicious lesions (19 cases) dense adhesions or anatomical conditions making laparoscopic surgery difficult (42 cases). 420 patients (444 cysts) were treated by laparoscopic surgery with either intraperitoneal cystectomy or transparietal cystectomy. The postoperative course following laparoscopic surgery for annexal cysts was uneventful in 417 cases (3 patients developed a complication).