Advances in the surgical approach to the anterior skull base have resulted in increased opportunity for the cure of tumors involving these structures. This paper describes a modification of the frontal craniotomy technique which allows excellent access to the anterior cranial fossa and orbit. This technique results in the en bloc removal of a bone flap which incorporates the orbital roof, superior orbital rim, and frontal bone. We have utilized this approach in 5 anterior skull base tumors (2 esthesioneuroblastomas, an angiofibroma, a case of orbital invasion by an aggressive inverted papilloma, and a squamous cell carcinoma of the ethmoid complex). This approach has the advantage of excellent exposure, clear visibility in the placement of chisel cuts, and less brain retraction than conventional techniques. It is the approach of choice for orbital tumors.