Two epidemiologic studies of spasticity at discharge and first annual follow-up in patients with traumatic spinal cord injury (SCI) are reported. Study 1 analyzed occurrence of spasticity and its severity for 96 subjects at one SCI center, with 67% of subjects developing spasticity by discharge and 37% receiving antispasticity medication. By follow-up, these figures were 78% and 49%, respectively. Incidence of spasticity was higher among cervical and upper thoracic than lower thoracic and lumbosacral levels of injury groups (p less than 0.001). Study 2 analyzed presence of spasticity severe enough to have warranted treatment on 466 subjects at 13 collaborating SCI centers, where 26% of subjects received treatment by discharge and 46% by follow-up. Probability of spasticity treatment was significantly related (p less than 0.05) to days from injury to discharge and level of injury group, whereas age, gender, and Frankel grade were not related. Among only cervical and upper thoracic subjects, Frankel grade was significantly related (p less than 0.01), with grades A (27%) and D (29%) being less frequently treated than grades B (50%) and C (52%). Importance of controlling the above significantly related factors is emphasized for future studies of methods to reduce incidence or severity of spasticity.