In most of the developed world, skilled women marry at a lower rate than less skilled ones. We document heterogeneity across countries in how the marriage gap between skilled and unskilled women has evolved over time. As labor market opportunities for women have improved, the marriage gap has been growing in some countries but shrinking in others. We discuss the comparative statics of a theoretical model in which the (negative) social attitudes toward working women might contribute to the relatively lower marriage rate of skilled women, and might also induce a non-monotonic relationship between their labor market prospects and their marriage outcomes. The model delivers predictions about how the skilled-unskilled marriage gap should react to changes in labor market opportunities across economies with more or less conservative attitudes toward working women. We verify the key predictions of this model in a panel of 26 developed countries, as well as in a panel of U.S. states.