Science abounds with unanswerable questions—those for which necessary data or even the necessary scientific methods are simply unavailable. Yet, for a variety of legal and political reasons, many such questions still require an answer. One way the Nuclear Regulatory Commission has cut this Gordian Knot has been through expert elicitation—a formal, highly structured, and well-documented process for obtaining the judgments of multiple experts. Yet, at least within the litigious context of nuclear energy regulation, this useful and creative process has been almost completely ignored by scholars, judges, and even the NRC’s own Commissioners. This article examines the Nuclear Regulatory Commission’s use of the expert elicitation process and provides an overview of both the process and the history of expert elicitation at the Commission from 1996 forward, and concludes with recommendations for its use of this process in the future. Although these questions, recommendations, topics, and sources are directed specifically to the Nuclear Regulatory Commission, they should also be useful to other agencies that likewise employ expert elicitation as a means of addressing otherwise-unanswerable questions.