A surgical technique (parasternal mediastinotomy) has been described which, with modifications, provides direct access to structures within the mediastinum. The procedure carries little risk for the patient and can be accomplished without disturbing pulmonary function or producing serious discomfort for the patient. We have utilized this technique in a total 152 patients for the diagnosis of indeterminate pulmonary lesions, evaluation of resectability of pulmonary neoplasms, biopsy of mediastinal structures including the heart, and insertion of permanent epicardial electrodes. Anterior mediastinotomy avoids the risks of formal thoracotomy and is of particular value in the treatment of poor risk patients. The use of this approach for placement of epicardial electrodes seems to have advantages over both the transthoracic and transvenous methods of permanent pacemaker implantation.