Complex and risky technologies--technologies such as new drugs for the treatment of AIDS that promise great benefits to our society but carry significant risks--pose many problems for political leaders and the policy makers responsible for overseeing them. Public agencies such as the Food and Drug Administration are told by political superiors not to inhibit important technological advances and may even be charged with promoting such development but must also make sure that no major accidents occur under their watch. Given the large costs associated with catastrophic accidents, the general...