The role of the expert witness in trials is a paradox. Judges and jurors need help with matters beyond their understanding, and judges are expected to act as gatekeepers to ensure that jurors are not fooled by misleading expert testimony. Yet, as gatekeepers, judges might not effectively distinguish sound from unsound expert testimony. As factfinders, judges and jurors both might have difficulty comprehending expert evidence, intelligently resolving conflicts between experts, and applying the scientific and technological evidence they hear to the larger dispute before them. This essay explores those problems and a variety of possible solutions, ranging from more effective ways parties might present technical information at trial, to educational interventions supervised by the court, to making juries more effective in performing their task, to more controversial measures, such as replacing conventional juries with special juries and replacing generalist judges with expert judges.