This article examines how some Catholic women, through their participation in an Acción Católica campaign, protested what they believed was the immoral nature of an expanding consumer culture: the movies, magazines, fashions, and comic books that inundated Mexico—particularly Mexico City—in the 1950s. Through this campaign, these women sought to construct an ideal form of Catholic womanhood that was both modern and moral—one that embraced modesty and sexual purity as a way for Mexico to modernize and progress. While the campaign had its roots in papal directives and was part of transnational discourses about morality, the Mexican women who participated saw their actions, nevertheless, in nationalistic terms. A modern Mexico, they argued, needed to have a strong moral base in order to be economically and politically successful; thus the morality they espoused centered on constraining women’s sexual expression.