We describe the diagnostic procedures and surgical approaches employed in 5 patients with dumbbell tumors of the mediastinum. Magnetic resonance imaging accurately described the existence and longitudinal extension of the intraspinal component of the tumor and assisted in choosing the appropriate surgical approach. Both the intrathoracic and intraspinal components of the tumor were resected at one time by a thoracic and neurosurgical team. We employed the Grillo technique three times and a separate laminectomy and thoracotomy approach. Magnetic resonance imaging proved the most useful diagnostic technique for suspected dumbbell mediastinal tumors. In our experience, the extended thoracotomy proposed by Grillo and co-workers worked well for small tumors involving only one foramen in which the intraspinal extension was limited to 2 to 3 cm, and when no more than two laminectomies were required. On the other hand, thoracotomy and a longitudinal paravertebral incision are preferable for larger tumors (more than 4 cm) involving more than one foramen in which the intraspinal extension exceeds 2 to 3 cm, for tumors requiring multiple laminectomy, and when bony infiltration is present.