We present patients treated for hydatid disease in our hospital (in northeastern Greece) over the last 20 years. In the period from 1984 to 2003, a total of 135 patients (54 male, 81 female) were treated for echinococcal disease (age 15-85 years). In 111 (82.2%) patients only the liver was affected; 9 (6.7%) patients had concomitant hepatic and extrahepatic hydatid disease; and 15 (11.1%) patients had only extrahepatic disease. Clinical symptoms in patients with hepatic locations of the disease included abdominal pain localized in the epigastrium or right upper quadrant of the abdomen, tenderness, hepatomegaly with palpable abdominal mass, jaundice, fever, and anaphylactic reaction. All the patients were treated surgically. Surgical techniques included partial cystectomy and drainage, cystectomy and capitonage, cystectomy and omentoplasty, only drainage, left lateral hepatectomy, total pericystectomy, and laparoscopic pericystectomy. Rupture into the bile duct was managed by T-tube drainage or biliodigestive anastomosis. Symptoms and surgical treatment for extrahepatic cysts varied according to the location of the cyst. The median cyst diameter of all patients was 11 cm. The postoperative complication rate was 17.0%. Two patients died (1.5%). The median hospital stay was 18 days. The recurrence rate was 6.7%. The study suggests that treatment of this benign disease should be the less radical surgical technique combined with pre- and postoperative anthelmintic administration. The surgical treatment should be combined with careful use of scolicidal fluids and aspiration of the cyst to avoid contamination and minimize the risk of recurrence.