Purpose: The value of high-cost health technologies is being increasingly scrutinized by providers of health care. An understanding of the costs and outcomes of high-technology epilepsy care is required to ensure efficient resource allocation. Methods: Decision analysis was used to estimate the cost effectiveness of anterotemporal lobectomy (ATL) as compared with standard medical management in medically-intractable epilepsy. Local (Rochester, NY, U.S.A.) cost data were applied to a model of lifetime discounted costs and outcomes of evaluation, ATL, and follow-up in a hypothetical cohort of patients. Results: Base case analysis yielded a marginal cost-effectiveness ratio (MECR) of $15,581/quality-adjusted life year (QALY). Extensive sensitivity analyses identified extreme conditions in which evaluation for ATL was dominant (more effective and less costly) or in which it might be considered not worth the cost (MCER >$50,000/QALY). Conclusions: Estimates of ATL cost effectiveness fall within a generally acceptable range, even when uncertainty about many model parameters is taken into account. Under assumptions based on available data in the literature, the cost effectiveness of ATL compares favorably with that of other health technologies. Prospective multicenter studies of regional cost and practice variations; long-term probabilities of year-to-year transitions between seizure outcome states and their effects on quality of life (QOL), and the effect of nonsurgical treatments on seizure control and QOL are needed to provide the critical data to confirm and constrain these estimates.