Ultrasound techniques have been developed since the past century and are becoming more useful in different areas of medical knowledge. More recently, lung ultrasound gained importance throughout artefact analysis to help clinical evaluation at bedside and became subject of interest in the pediatric intensive care and emergency department settings for both procedural and diagnostic purposes. The normal pattern of lung ultrasound is defined by the presence of lung sliding associated with A-lines whereas B-lines may be representative of pathology findings. This review focuses on some of the most common pulmonary conditions, their respective sonographicfeatures and clinical implications in the emergency department and pediatric intensive care unit. There have been a number of recent advancements in the field of point-of-care ultrasound, including lung ultrasound for pediatric populations. Evidence- based guidelines on the use of point-of-care lung ultrasound have been published. Lung ultrasound is superior to chest radiography in diagnosing several disorders. Before performing lung ultrasound, it is important to note that the position of the patient could affect the findings, as air increases and liquid sinks under the influence of gravity, lung ultrasound is usually performed with the patient in the supine position. While lung consolidation or pleural effusion is predominantly found in dependent and dorsal lung regions, pneumothorax is primarily found in the anterior chest.