A series of twenty-seven patients with diastematomyelia was analyzed with respect to presenting complaints, physical findings, roentgenographic findings, and treatment. Particular attention was directed to the problem of the associated spinal deformity; twenty-six patients had significant spinal deformity, sixteen of whom required spine fusion. A 4.9 per cent incidence of diastematomyelia in congenital scoliosis was noted. Surgical removal of the bone spur tended to prevent increase in neurological deficit but seldom improved the neurological status. Surgical treatment of the scoliosis should be delayed until after removal of the septum.