The purpose of the study was to analyze the relative cost of selective functional posterior rhizotomy (SFPR) and continuous intrathecal baclofen in the treatment of children with severe spastic quadriplegia related to cerebral palsy. No attempt was made to analyze the efficacy of the two types of treatment. Nine children with spastic quadriplegia secondary to cerebral palsy in whom continuous intrathecal baclofen was attempted were matched as closely as possible with a group of 10 patients with spastic quadriplegia out of a total of 100 children who had undergone SFPR in the same time period. Clinical care flow charts were created to identify the various points of contact with members of the health care team, so that cost points could be identified and costs calculated. The cost per patient up to 1 year a after treatment CDN$ 64,163.10 for patients with implanted pumps for continuous intrathecal baclofen versus CDN$ 16,913.54 for SFPR. When adjustments were made to exclude costs and savings associated with research protocols, the average for the baclofen group decreased to approximately CDN$ 63,000, with minimal change for the SFPR group. The higher cost per patient on baclofen was related to the cost associated with screening patients who did not go on to have implantation of a continuous infusion pump, and to additional hospitalization for complications in the baclofen group. It is cautioned that this cost analysis was based on the experience at British Columbia's Children's Hospital, and the results may not be generalizable to other institutions or to other patient populations.