The clinical and radiographic features of spinal cord dysfunction secondary to Paget's disease are described. Long-term medical management with the use of the diphosphonates, calcitonins and mithramycin resulted in marked and rapid clinical improvements in 8 of 10 of our own patients. These results are comparable to those seen in 19 other patients previously described in the literature, and are also similar to those obtained by surgical treatment. The recurrence rate and mortality (approximately 10%) of surgical treatment suggest that drug treatment now has a place in the management of paraparesis, particularly when this is of gradual onset. Medical management may also provide a valuable adjunct in those cases where surgery is required (e.g. sudden onset of paraparesis). In patients with cord dysfunction, but without significant anatomical compression of the spinal cord, it is suggested that paraparesis may be caused by a "vascular steal" syndrome, a notion which is supported by the rapidity with which drug-induced remission occurs.