Using a sample of 200 emerging adult male college students, we examined how men varied in the meanings they gave to sex and their self-reported engagement in two types of casual sex relationships (hookups and friends with benefits). Using qualitative methods, we conducted a content analysis of men's written responses to a series of questions about the meanings they ascribed to sex (i.e., intercourse), their perceived connection between sex and commitment, and how they believed these meanings were related to their sexual behavior. Three groups of men emerged: Committers, Flexibles, and Recreationers. Groups were then compared on social desirability, demographic characteristics (e.g., race/ethnicity, year in school, religious service attendance), and self-reported casual sexual behaviors in the past 12 months. Analyses showed that men in the Flexibles and Recreationers groups engaged in significantly more hookups and had significantly more friends with benefits partners in the past 12 months than did men in the Committers group. Implications for relationship education intervention aimed at men and research on casual sex relationships are discussed.