Estrogen (ER), progestin (PGR), and androgen (AR) receptors were assayed in cytosols prepared from 38 various intracranial tumors. The receptors were in the following proportions (number of receptor-positive/number of tumors examined): meningiomas were positive for PGR (4/6) and AR (2/5); glioblastomas were also positive for PGR (3/21) and AR (7/21); astrocytomas were positive only for PGR (4/5); and oligodendrogliomas only for AR. In two hamartomas AR was present, while in one chordoma both PGR and AR were present. In this latter tumor ER were not assayed due to insufficient material. The receptors were present in concentrations between 10 and 20 fmol/mg protein. Exceptions were two meningiomas and a chordoma with a high concentration of PGR and AR. Our results support the notion that a proportion of intracranial tumors contains sex steroid receptors, and some of these tumors might be hormonally dependent.