Skull-base imaging has been a key factor in the advancement of skull-base surgery. The analysis of MR imaging or CT of the skull base emphasizes important landmarks, which are key to surgical planning. Although the definitive diagnosis usually is done by biopsy, the radiologist can limit the list of possibilities of the identity of a skull base lesion. The apparent site of origin is a key factor. Separation of cystic abnormalities from more solid enhancing abnormalities also is critical.