The law requires the existence of a reasonable belief of imminent harm to establish the claim of self-defense. Because many battered women kill their husbands when they can catch them off guard, their actions fail to meet the traditional imminency requirement. To aid battered women in successful self-defense assertions, attorneys and psychologists have attempted to introduce through expert testimony evidence of the battered women's syndrome, which results in distorted perceptions of imminent harm during times when the traditional self-defense claim would not apply. The lack of adherence to a uniform body of evidentiary rules, however, has resulted in conflicting rulings on the admissibility of such evidence. Although there have been several attempts at adopting uniform rules of evidence, States still maintain their own unique evidentiary procedures. Federal Rule 702 presents a two-part test requiring the expert to be qualified through knowledge, skill, experience, training, or education and to be able to help the trier of fact understand the evidence or determine a fact in issue. The conflict between the courts over the admissibility of expert testimony about the battered woman's syndrome in homicide trials could be resolved by uniform adoption of this rule. This would permit the admissibility of such evidence, subject to factors related to the reasonableness of the defendant's belief that she was in imminent danger. In determining admissibility, the judge should be presented with facts sufficient to show that the defendant had been a victim of a history of batterings. The judge should also consider the time lapse between the beatings and the killings. A total of 170 footnotes are provided.