In a Dutch national study, we recently established the effectiveness and safety of continuous intrathecal baclofen infusion (CITB) in children with intractable spastic cerebral palsy (CP). Because prospective studies on the costeffectiveness of CITB in children with spastic CP are lacking, we conducted a cost-effectiveness analysis alongside our prospective national study. We compared the costs and health effects of CITB with those of standard treatment only, from the health care perspective for a 1-year period. Health effects were expressed in terms of a visual analogue scale for individual problems and quality-adjusted life years (QALYs). We included eight females and seven males, aged between 7 and 17 years (mean age 13y 8mo [SD 3y]). Eleven children had spastic CP and four had spastic-dyskinetic CP. One child was clsssified on the Gross Motor Function Classification System at Level III, two at Level IV, and 12 at Level V. CITB was more effective and more costly than standard treatment only. Gaining one QALY cost on average €32 737. We conclude that based on the threshold-willingness to pay for one QALY in the Netherlands (€80 000), our results confirm the cost-effectiveness of CITB for carefully selected children with intractable spastic CP.With a prevalence of about 2 per 1000 live births in Western countries, cerebral palsy (CP) is the most common cause of severe physical disability in childhood. 1 Spasticity accounts for 70 to 91% of the motor disorders associated with CP and is intractable in a substantial group of children. 2 Intractable spasticity can cause pain, sleep disturbances, increased energy requirements, pressure sores, and interference with positioning, transfers, dressing, and body hygiene. Besides the negative impact on quality of life, serious spasticity involves high costs. In a cost of illness study, we estimated the mean annual societal costs in Dutch children with intractable spastic CP at €40 265. 3 This is more than 11-fold the mean expenditure for care per Dutch capita. 3 In a prospective Dutch national study, 4-6 we recently established the effectiveness and safety of continuous intrathecal baclofen infusion (CITB) in children with intractable spastic CP. Our randomized controlled trial showed that CITB significantly improved individually formulated problems, ease of care, pain, and gross motor functioning. Moreover, healthrelated quality of life (HRQL) significantly improved for the domains of bodily pain/discomfort, mental health, psychosocial status, and parents' personal time limitation (M A Hoving, personal communication 2007). Our results are in keeping with those of non-randomized trials. 7 Health care expenditure is rising and resources (people, time, facilities, equipment, and knowledge) are scarce. Decision makers, including policy makers, health care insurers, health care providers, and even patients, consider information on both costs and effects when choosing between different interventions. One way to control health care costs is to apply a transparent and rational de...