Why do some Muslim women adopt fundamentalist islamic value systems that promote gender-based inequalities while others do not? this article considers the economic determinants of fundamentalist beliefs in the Muslim world, as women look to either marriage or employment to achieve financial security. using cross-national public opinion data from eighteen countries with significant Muslim populations, the authors apply a latent class model to characterize respondents according to their views on gender norms, political islam, and personal religiosity. among women, lack of economic opportunity is a stronger predictor of fundamentalist belief systems than socioeconomic class. cross-nationally, fundamentalism among women is most prevalent in poor countries and in those with a large male-female wage gap. these findings have important implications for the promotion of women's rights, the rise of political islam, and the development of democracy in the Muslim world.