We have demonstrated that replication-competent attenuated mutants of herpes simplex virus type 1 (HSV-1) have therapeutic potential for malignant gliomas. Moreover, a recently described multiple mutant HSV (termed G207) has properties which may allow human clinical trials. G207 is able to replicate within and kill cells from three human malignant meningiomas in cell culture. In nude mice harboring s.c. human malignant meningioma (F5), G207 can inhibit growth in a dose-dependent fashion. In nude mice harboring intracranial subdural human malignant meningioma (F5), one injection of G207 caused significantly decreased tumor growth and one apparent cure with neither neurological dysfunction nor pathological changes in the surrounding brain. These results suggest that G207 should be considered for therapeutic trials in the treatment of malignant meningioma refractory to currently available therapies.