In studying the behavior of students who trade digital files, such as MP3s, over the internet, we have identified a number of gender differences. These differences are interesting because they reflect broader issues such as differences in technology use, cooperative behavior, and risk aversion. MP3s are highly-compressed, high-quality digital audio files that are easily reproduced, and are traded over the internet using special peer-to-peer (P2P) software. Such file trading is frequently at odds with copyright law. We surveyed nearly 1,300 economics principles students at three universities: Colorado State University, Southwest Missouri State University, and the University of Missouri-Rolla. Such students represent a key segment of the file-sharing population. We examined gender differences relating to the uploading and downloading of MP3s from non-commercial sources. Of the 1,239 students who indicated their gender, 501 are female. Certainly, men and women in the sample are similar with regard to several relevant characteristics. For example, no statistical differences between their ages, computer ownership, or reported level of total monthly expenditures exist. However, there were differences in listening habits and computer use. Women in our sample listen to 3.7 hours of music a day, while the men spend only 3.4 hours, a difference significant at the 5 percent level. Women do spend significantly less time on the computer each day. Despite their greater listening habits, fewer women own MP3s. While 84 percent of the men own MP3s, only 68 percent of the women do. A t-test suggests the difference is significant at the 1 percent level. Furthermore, even among those who already own MP3s, men indicate that they expected to obtain significantly more MP3s in the future than the women. When asked how many songs in MP3 format they are expected to acquire in the next 12 months, women are over-represented in the categories of none and 1Y100, while men are over-represented in the categories of 300 or more. File trading requires a certain level of cooperative behavior. To have a robust supply of files for downloading, somebody must be willing to upload. When asked whether they made their digital song files available to others, of those who answered the question, 65 percent of the men but only 51 percent of the women indicated they did. A Pearson Chisquared test rejects the hypothesis that making MP3s available is independent of gender at the 1 percent level. Other research used a logit model to show that female students were only 65 percent as likely as their male counterparts to make MP3s available to other users, even after controlling for such things as time spent listening to music, time spent on computers, and the desire to download more MP3s. [Gallaway et al., Journal of Economics, 2006]. However, male and female students are remarkably similar in their understanding of the free rider problem. Roughly 71 percent of both women and men Atlantic Economic Journal (2006)34:509Y510 * IAES 2006 DOI: 10.1007/s11293-006-9034-x