One of the most significant advantages held by female terrorists is that their potential is denied, ignored, and diminished and as a result they are almost always unanticipated, underestimated, and highly effective. Their effectiveness results from an important nexus: the ingenuity and capabilities of female attackers, the rational calculations and organizational capabilities of terrorist organization leaders, and the shortsightedness and denial of officials in the targets. The cases examined in this study demonstrate the importance of all three features but the only area that officials truly have the power to correct is their own. Counterterrorism efforts need to be directed toward learning from the past to anticipate potential futures. Initial steps can be taken in the six counterterrorism deficiency areas that emerged from existing cases of female militancy: exploitation, organization, technology, denial and deception, tactical advantages, and culture and ideology. Women represent a growing presence in countless terrorist organizations officially identified as national security threats to their respective states. This analysis briefly explores three cases (the United States, Israel, and Russia) involving high levels of female involvement in organizations that are officially viewed as pressing terrorist threats. All three cases involve conservative/traditional socio-ideological settings or organizations that observers often view as especially hostile to female participation and activism. Utilizing some of the counterterrorism lessons of these cases, this analysis explores how addressing these deficiencies may improve counterterrorism efforts by examining two cases that have considerable potential for female militancy and violence in the future--the left wing terrorism in the United States and global Islamist terrorism by groups like al Qaeda. Notes, references