Liver hydatidosis is the most common clinical presentation of cystic echinococcosis (CE). Ultrasonographic mass surveys have demonstrated the true prevalence, including the asymptomatic characteristic of the majority of cases, providing new insight into the natural history of the disease. This raises the question of whether to treat or not to treat these patients, due to the high and unsuspected prevalence of CE. The high rate of liver/lung frequencies of cyst localization, the autopsy findings, and the involution of cysts demonstrated in long time follow-up of asymptomatic carriers contribute to this discussion. The decision to treat an asymptomatic patient by surgery, albendazole, or puncture aspiration injection and re-aspiration or to wait and watch, is based on conflicting reports in the literature, the lack of complications in untreated patients over time, and the spontaneous disappearance and involution of cysts. All these points contribute to difficulties of individual clinical decisions. The patients should be informed of the reasons and the risks of watchful/waiting without treatment, the possibility of complications, and the risks of the other options. As more information on the natural history of liver hydatidosis is acquired, selection of the best treatment will be come easier. Without this knowledge it would be very difficult to establish definitive rules of treatment. At present, it is possible to manage these patients over time and to wait for the best moment for treatment. Follow-up studies must be conducted to achieve this objective.