In 221 patients (0.48% of hospital admissions) with hydatid disease (122 female and 99 males), 81% had single and 19% multiple organs involved. Lungs, liver and spleen as single sites of echinococcosis together represented 83.24% of cases and the liver alone represented 95.24% of instances with multiple organ involvement. One hundred seventy-nine single and 74 multiple cysts (ratio of 2.42/1) represented a total of 363 cysts (1.64 cysts/patient). The incidence of intact cysts was 51.52% and 48.48% had ruptured. Ruptures numbered highest in the lungs (73.44%) and greater in multiple (79.66%) than in single cysts (68.12%). In the liver, 27.14% of single and 54.55% of multiple cysts (40.44% of all liver cysts) had ruptured. Cysts varied in size from 0.8 to 35 cm diameter. Single cysts averaged significantly higher (14.16 cm) and multiple ones lower (5.71 cm) as did intact (6.75 cm) versus reptured cysts (4.33 cm). Except for 10 silent and 15 symptomatic cysts treated medically, all the rest were treated surgically by removal of the endocyst or resection of both endo and exocysts including 205 first, 31 second and 5 third procedures (1.75% of all major operations). Complications occurred in 28.57%. Surgical mortality (3.57%) was markedly lower than with conservative treatment (60%) and significantly less than that of the whole group (14.48%).