The aim of this study is three-fold: (1) to examine the similarities and differences between instructor and peer assessments of EFL group presentations; (2) to understand the utility of peer assessment for discriminating each group member's contribution to group presentations in college EFL classrooms; and (3) to investigate the relationship between the quality of a group product and group cooperation, each of which were measured by peer assessments. Eighty-three Japanese freshmen worked in groups to create TV commercials. They then completed two types of peer assessment. Results indicated an overall similarity between peer and instructor assessments, along with some notable differences in item difficulties. Most group members succeeded in differentiating the degree of each member's contribution to the group project. Strong support, however, was not found for the assumption that groups with high cooperators produced quality group presentations. Although these results are encouraging for using peer assessment for EFL group presentations, some caution is advised. (Contains 7 tables and 1 figure.)