Relatively little is known in existing research about how cooperative education (co-op) students experience mentoring. The parameters within which co-op students are employed are different from those of full-time professionals. Co-op students are temporary employees, and they are typically younger and have less professional experience than full-time employees. Co-op students also may complete each of their three work terms at a different company site. These unique characteristics of co-op students and co-op employment could prevent the direct application of known mentoring practices to the co-op setting. Further research on the intricacies of mentoring as it is experienced by co-op students could yield a set of mentoring best practices to be used by co-op employers and university co-op administrators. The purpose of this study was to compare organizational commitment, mentoring satisfaction, and mentoring function levels of co-op students according to mentoring type (formal and informal) and work term number. Participants were undergraduate engineering students at a large public land-grant university in the Southeast United States. The research design was causal-comparative; an online survey composed of existing instruments was used to capture student perceptions of mentoring experiences during recently completed work terms. Mentoring activity was found to be high, with 92.8% of students reporting involvement in a mentoring relationship. Students who were mentored showed higher organizational commitment than students who were not mentored. Students who reported higher levels of organizational commitment also reported an intention to stay with the company after graduation if offered a full-time position, but student satisfaction with mentoring did not share a relationship with intention to stay. Students were also equally satisfied with their mentors regardless of mentoring type (formal or informal). Student perceptions of psychosocial support increased as the number of work terms completed increased, and students in formally arranged mentoring relationships reported higher levels of psychosocial support than students in informal mentoring relationships. The type of mentoring was not related to any differences in mentoring outcomes. The researcher concluded that companies that want to convert co-op students into full-time employees should ensure that these students receive positive mentoring experiences during their co-op work terms.