The present study is comprised of two parts: 1) an exploratory ethnography of a contemporary polygynous community governed by a strong patriarchal ideology in Pinesdale Montana with emphasis on social relationships, and 2) an analysis of the factors which have allowed women's groups to develop in Mormon fundamentalism. The ethnographic account of the community contextualizes the occurrence of female groups in Pinesdale. A model of the formation of female groups designed by Nancy Leis (1974) in her study of the West African Ijaw is used to provide a better understanding of how female groups are formed, and is applied to the Pinesdale community. This model suggests that the combination of features relevant to the occurrence of female groups are virilocality, patrilineality, polygyny, and economic independence. In spite of the kin-based nature of her African study, which limits its applicability to Western society, Leis suggests that her model "would predict the presence or absence of women's groups elsewhere," and encourages a cross-cultural study to prove her hypothesis. My thesis investigates the strengths and limitations of Leis' model within an ethnographic framework.