The adverse expert is typically the most dangerous witness and, at the same time, the most vulnerable. Most dangerous because he testifies cloaked in the mantle of the "unbiased scientist"; thus, his testimony - if accepted by the jury - can determine an issue, maybe the entire case. Yet, most vulnerable because, unlike the fact witness who must defend only his first-hand observations, the expert witness must defend his testimony from attacks on multiple fronts. This seminar analyzes and illustrates dozens of archetypal attacks against the adverse expert's pedestal-like status.