Rules 413-415 would liberalize the admissibility of "propensity evidence" in criminal and civil cases that involve allegations of sexual assault and child molestation. The article recommends that if some version of the proposed rules is to be retained, the rules at least should be amended to limit admissibility to evidence of prior convictions for sexual assault or child molestation. This change would avoid some of the worst potential abuses that may arise from the use of unsubstantiated charges as a basis for an inference that a defendant has a propensity to offend and thus that he or she is guilty of the offense at hand. This change would also keep trial judges from having to conduct numerous disruptive, confusing, and time- consuming "mini-trials" on the validity of each allegation of prior misconduct. For these and other reasons, the author recommends that the character rules in the Federal Rules of Evidence should be left intact. Generally, the article concludes that the particular changes proposed are overbroad, potentially unconstitutional, and poorly drafted. A more modest change would include compulsive, but not other prior or subsequent, sexual assault and child molestation within the definition of habitual conduct that the Federal Rules of Evidence currently make admissible to show action in conformity. If the proposed rules are to become effective in their current form, then modifications should be made to integrate them within the structure of the Federal Rules of Evidence and to cure various drafting anomalies. 28 footnotes