Since little is known about the erotic fantasies during coitus of younger women and men, data were collected from a sample of college students to determine the frequency and type of fantasy in this population. Fantasizing during sexual intercourse was reported by the majority of the respondents of both sexes. Males reported fantasizing early in their coital experience and reported more fantasies involving an imaginary lover than did the females. Women reported more fantasies of being forced into sexual relationships and themes involving a member of the same sex than did men. Both sexes reported the primary purpose of the fantasies was to enhance sexual arousal. The results are interpreted as indicating that fantasizing during coitus is a normal component of sexual behavior. © 1979, Taylor & Francis Group, LLC. All rights reserved.