This retrospective study was carried out to evaluate the indications for and outcomes of the hemiclamshell (HCS) approach (longitudinal partial sternotomy with antero-lateral thoracotomy) in patients undergoing mass resection in thoracic surgery. All patients (50) who underwent a HCS procedure in our department, between July 1996 and July 2005, were studied retrospectively, analyzing the indications, morbidity and outcome (pain, neurological or shoulder defects, mortality) at one month and one year. The main indications were apical tumours (38%), tumours of the cervicothoracic junction (46%) and chest wall (10%), and 'bulky' tumours (6%). One-month mortality was 6%. Two patients suffered from a chylothorax and one from phrenic paralysis. The postoperative analgesic requirements were similar to those after other thoracic surgery approaches. Twelve percent of patients suffered pain at one month and 6% at one year. Shoulder dysfunction was observed in 10% of patients at one month and 6% at one year. In conclusion, the HCS surgical approach was associated with an uncomplicated postoperative course. This anterior approach is suitable for apical tumours, tumours of the cervicothoracic junction and 'bulky' lung tumours, providing good access for control of the large vessels and radical mediastinal clearance.