This study examines the relationship of social-comparison concern, comfort, and self-efficacy to course performance and program persistence in a small-group learning environment. As part of the study, 205 undergraduates in a peer-led, small-group science learning program were surveyed at the beginning and end of the academic term; surveys addressed self-efficacy for the course, comfort participating in the small groups, and concern about comparison with others in the groups. Results indicated that while social-comparison concern and comfort were unrelated to prior academic preparation (as measured by grade point average and SAT mathematics score), they were related to self-efficacy, ethnic minority status, and gender, as well as to persistence in the program and final grade. (Contains 5 tables, 1 figure, and 1 footnote.)