Thoracic endometriosis syndrome encompasses a spectrum of clinical and radiological manifestations associated with the growth of endometrial glands and stroma in the lungs or on the pleural surface. TES encompasses four clinical entities, involving catamenial pneumothorax, catamenial hemothorax, catamenial hemoptysis, and pulmonary nodules. Catamenial pneumothorax is the most common clinical presentation, and the right hemithorax is affected far more often than the left hemithorax. Multiple mechanisms have been proposed to explain the pathogenesis of catamenial pneumothorax, including spontaneous rupture of blebs, transdiaphragmatic passage of air, sloughing of endometrial implants from visceral pleura with subsequent air leak, and alveolar rupture caused by prostaglandin-induced bronchoconstriction. Video-assisted thoracoscopy (VATS) is the gold standard modality for definitive diagnosis and surgical treatment of catamenial pneumothorax. More than half of patients with catamenial pneumothorax assessed with VATS are diagnosed as having thoracic endometriosis. Diaphragmatic abnormalities (fenestrations or endometriosis, alone or combined) are the most commonly described lesions, followed by endometriosis of the visceral pleura, discrete lesions, such as bullae, blebs, and scarring, or no findings are noted. In this video, we present the case of a 40 year old para 2 with history of extensive endometriosis and new onset cyclic chest pain and worsening pelvic pain, not responsive to hormonal therapy. She underwent video-assisted thoracoscopy with wedge resection of the affected lung tissue and pathology was consistent with endometriosis.