188 Women and the Transmission of Religious Knowledge in Islam quantity of women’s roles. Finally, most women who are credited with traditions after the time of the Companions had died by 150 AH, which suggests that in early Islam, what little there was of women’s hadith participation was limited to the first century and a half. There are a handful of obscure women credited with transmission in the final quarter of the second century. Thereafter, no women appear in the isnads of the selected compilations. Multiple sources substantiate and nuance this picture of stark decline that emerges from the isnad evidence. Chronicles and biographical dictionaries drawing on a broader array of sources round out the picture. For example, both the Tabaqat of Ibn Sa‘d and the Ta’rikh Dimashq of Ibn ‘Asakir contain entries for female transmitters who do not appear in the isnads of the selected compilations. However, most of these women are again from the generations of the Companions or early Successors. Similarly, none of the biographical dictionaries and chronicles consulted for this research indicates significant levels of women's participation from the second/eighth to the mid-fourth/tenth century. Thus these works confirm simultaneously the selectivity inherent in the hadith compilations chosen for this study as well as the historicity of the patterns of decline observed in the isnad data. In making sense of this marked decline, we might at first suspect explicit discrimination against women. A few discussions recorded in second/ eighth-century legal manuals such as the Kitab al-Hujja of al-Shaybanl do show that the sex of the narrator, regardless of whether she was a Companion or not, could diminish the value of a tradition in legal discussions. Thus, some women’s narrations, particularly on highly contested issues, were stigmatized on the basis of gender. Yet such references are scattered and do not fully account for the pervasive and profound marginalization of women over two and a half centuries. Several other impediments derailed women’s participation. The early second/eighth century witnessed the beginnings of the “professionalization” of hadith transmission in the course of which rigorous criteria came to be applied to judge the quality of an individual’s transmission. This development placed a high bar on entry to the field, favoring those who demonstrated legal acumen and who acquired training through extensive individual tutelage with other leading scholars. Cultural and religious norms curtailing women’s interactions with non -mahram men hampered women’s acquisition of the requisite training. Around the same time, undertaking strenuous journeys to collect hadith ( rihlas ) became critical for the success of a hadith scholar. Women’s limited mobility, again