A persistent air leak is most commonly caused by a secondary spontaneous pneumothorax from underlying lung disease. There are several treatment options, which also depend on the underlying cause. Possible treatment options include conservative measures (larger-bore chest drains, pleurodesis) or surgical treatment. However, if this is not possible or unsuccessful, there are several bronchoscopic options. The source of a peripheral air leak can be localized with sequential balloon occlusion. If the involved segments are identified, these bronchial segments can be blocked to decrease the airflow and promote healing of the fistula. There are several endobronchial treatment options for closing the subsegments. Use of endobronchial valves has been described the most, but also the use of Watanabe spigots or other blocking devices, or tissue adhesives can be considered.