A Zenker’s diverticulum (ZD) is a herniation of the proximal oesophagus. Patients often have complaints of swallowing or regurgitation, but the diverticulum can also be asymptomatic. We present the case of a patient with an undiagnosed ZD. The ZD was discovered after a nasogastric tube perforated the diverticulum and pleural fluid was aspirated through the tube. We discuss the patho- physiology, diagnosis and treatment of a ZD, as well as methods of confirming correct placement of nasogastric tubes.