General session 4 of a 2010 scientific symposium sponsored jointly by the Society of Toxicologic Pathology and the International Federation of Societies of Toxicologic Pathologists considered the problem of primary neoplasms of the nervous system, especially the brain and spinal cord. Primary tumors of the nervous system account for a small but persistent fraction of cancers, occur disproportionately in juveniles, and are notoriously difficult to treat. This session explored new ideas and techniques with respect to the etiopathogenesis, diagnosis, and treatment of neural tumors with an emphasis on the translation of animal models of brain neoplasia and toxicology investigations for candidate therapeutic agents to the human situation. Additionally, this session covered current thinking on pharmaceutical discovery and safety assessment that is unique to this area of oncology.