Ultrasound (US) has been used for in-hospital evaluation of the trauma victim for many years. The outcome in severely injured patients remains heavily influenced by initial life support and early care, as time plays a major role. Development of handheld, battery-powered, low-weight US machines has created the possibility of bringing US to the prehospital setting, thus gaining a potential for early diagnosis and treatment. The objective of this study was to systematically search the literature for evidence that prehospital US of the abdomen or thorax increases survival of trauma patients. The data regarding the use of US in the prehospital setting is sparse, often of low quality and describing a broad variety of patients and clinical challenges. Therefore, from an evidence point of view it is not possible to answer the objectives in this review. In the prehospital setting, rapid assessment plays an important role, as initial life support and early surgical care influences the outcome of the severely injured patient. Time is especially crucial in blunt abdominal trauma and penetrating truncal injuries. Several studies in this review showed that prehospital US is feasible and that the procedure is highly reliable in detection of haemoperitoneum or haemopericardium compared with the low accuracy of physical examination and haemodynamic measurements. An early diagnosis will provide the prehospital physician with the knowledge to prioritize the relevant initial treatment and to choose the closest appropriate hospital and transportation form. There is currently no evidence in the literature that prehospital US of the abdomen or thorax improves treatment of trauma patients.