Pharmacogenomics requires a reexamination of the justification of medical liability doctrines. The traditional justification of balancing the risks and benefits of medical intervention to individual patients should be replaced by a new theory of how after-the-fact adjudication balances the risks and benefits to groups. Liability doctrines must incorporate a systems approach in imposing or withholding liability. The underlying rationale of medical liability must be rethought with the primary goal of providing some incentives for those involved in the development, distribution, and dispensing of the products of pharmacogenomics to incorporate systemic approaches to risk reduction.