Numerous routes of access to the medial basal structures of the cranium have been described, largely because of the wide variety of lesions observed in deep localizations. Access can be achieve via trans-sinusal, transfacial (trans-sphenoidal rhinoseptal, mediofacial or Lefort I), trans-oro-pharyngeal and numerous other routes. An examination of the principals involved, their development and the technical modalities demonstrate the advantages and disadvantages of each and their specific indications. Access is particularly interesting with the frontal trans-sphenoid, Lefort I osteotomy and trans-oro-pharyngeal routes. The simplicity of these non-mutilating routes provide an alternative to neurosurgical access. Their development depends on progress in imaging and microscopic surgery. Used alone or in combination, they can be an useful complement to a neurosurgical access.