Examination of the cerebrospinal fluid (CSF), and myelography, were performed in most of 89 consecutive patients with X-ray evidence of vertebral metastases to test the value of these examinations in the early detection of neoplastic involvement of the epidural space. Patients were divided into 3 groups. In 7 cases (group I), the vertebral metastases were asymptomatic. Fifty-nine (group II) had symptoms or signs of radicular lesions but not of spinal cord compression. Twenty-three showed various stages of spinal cord or cauda equina compression (group III). Involvement of the epidural space was demonstrated on myelography in almost 50% of patients from groups I and II by a partial (29%) or complete (19%) arrest of the opaque medium. In addition, five patients in group II with normal myelograms had increased levels of CSF protein. Leucocyte counts were within normal limits in all patients. Neoplastic cells were found in two cases. It is suggested that in patients with only radiological evidence of neoplastic involvement of the epidural space and complete myelographic blocks, laminectomy, followed by radiation therapy, should be performed. Patients showing partial blocks should receive radiation therapy only.