The literature concerning intrathecal herniation of intervertebral discs is briefly reviewed. 2. A case of an intrathecal herniation of a cervical disc with transitory paraplegia and a following Brown-Sequard-Syndrome is reported. 3. Laminectomy disclosed a rotation of the cord and a sequestrated disc embedded in the anterior substance of the cord. 4. A trauma of the cervical spine 8 years ago seem to be responsible for the progredient protrusion of the cervical disc. 5. Adhaesions between the dura mater and posterior longitudinal ligament in this case are regarded as origin of intrathecal herniation.