Summary: The diagnosis of respiratory tract diseases, which are the most common cause of pediatric appointments, is based on clinical examination. For a long time, diagnostic imaging has been performed by means of classic chest radiography, despite the exposure to roentgen ionization. Nowadays, ultrasound examination, which is a noninvasive, cheap, and fast alternative, has become widely available. In addition, it does not require specialized tools, and the basic diagnostic skills can be acquired after just a few hours of training. Therefore, ultrasonography-based diagnosis and monitoring of respiratory system diseases is suitable both for pediatric ambulatory care and for hospital emergency rooms. In some ways, ultrasonography can be considered the “stethoscope of the future.”