Ultrasound has been revolutionising our specialty. The introduction of new, portable machines and goal-directed protocols has led many anaesthetists to use this diagnostic tool in their daily practice. Immediate, bedside ultrasound diagnosis of many life-threatening emergencies (pneumothorax, cardiac tamponade, or internal haemorrhage) enables not only the institution of proper treatment, but also the monitoring of its effectiveness. Ultrasound guided invasive procedures (such as vascular cannulations, toraco- and pericardiocentesis) have superseded the old anatomical landmarks-based techniques due to a greater safety margin. In order to perform a credible ultrasound examination, a proper level of competence is required. In this review article, the authors present various critical ultrasound applications.