SummaryTransthoracic ultrasonography is a well-established, yet underutilised imaging modality in respiratory medicine. It allows for real-time and mobile assessment of thoracic disorders and can potentially augment the physical examination of the chest. Moreover, ultrasonography-assisted interventions can be performed by a single clinician without sedation and with minimal monitoring, even outside of the operating theatre. Other advantages of chest ultrasonography include the lack of radiation and the short examination time. Many indications for the use of ultrasonography beyond the visualisation of the pleura and related conditions (including effusions, thickening and pneumothorax) have been validated in the last few decades. These include the assessment of diaphragmatic dysfunction, pulmonary consolidation, interstitial syndromes, pulmonary embolism, and pulmonary and mediastinal tumours, provided they abut the pleura. Transthoracic ultrasonography is an ideal guide for thoracocentesis. Ultrasonography-assisted fine-needle aspiration and/or cutting-needle biopsy of extrathoracic lymph nodes, and lesions arising from the chest wall, pleura, peripheral lung and mediastinum are safe and have a high yield in the of hands of chest physicians. Ultrasonography may also guide aspiration and biopsy of diffuse pulmonary infiltrates, consolidations and lung abscesses, provided the chest wall is abutted. This review will focus on the basic indications and applications for transthoracic ultrasonography.