The management of the trauma-emergency patient has become an important political and economic issue and one of the major challenges of the industrialized countries. In Europe ultrasonography is always part of the basic work-up, following physical examination, whereas computed tomography (CT) remains a second-line investigation. Injury prevalence, radiation dose exposure, practicability, and costs are relevant considerations in our emergency departments, where we have a growing number of patients seeking medical attention. The radiologist's task is to decide which imaging modality is most appropriate after the clinical context has been taken into consideration. The clinical value of CT is unquestioned; what is questionable is only its systematic use. With the growing demand for trauma care, screening ultrasonography can lower the number of inappropriate CT examinations.