The morbidity of thoracotomy is reduced by thoracoscopy. The space for dissection is obtained by collapsing the lung. During posterior mediastinal procedures the patient is positioned prone. This allows the collapsed lung to fall away from the field of dissection. In face of conversion to lateral thoracotomy re-positioning will take time, which may be dangerous like in a severe bleeding. An alternative is to place the patient semi prone and get in to a near prone position by tilting the table. Quick return to lateral position can be achieved by tilting the table in reverse direction. Upper thoracic sympathectomy and mobilization of thoracic oesophagus were done in the adopted prone position. Bilateral splanchnicectomy was performed in the prone position. In both situations, there was adequate space for instrumentation and dissection. Retractors were not required. All the procedures were completed safely with minimal blood loss and an acceptable time. There were no conversions. Therefore, the advantages of prone position to provide space for dissection in posterior mediastinal thoracoscopic surgeries were obtained by the adopted semi prone position.