This study investigates the impact of peer assessment on students' engagement in their learning in a group work context. The study used regression analysis and was complemented by qualitative responses from a survey of 165 first-year undergraduates in a UK university. Findings suggest that students' perception of their contribution to group work fosters engagement and enhances their learning in a group. Also, that students' perception and the overall experience of rating their peers' work impact their engagement within a group. The study contributes to the literature by focusing on the assessment of the entire learning journey within a group rather than the final group output. In particular, the study highlights the significant contributions of peer assessment in managing student engagement in modules and/or assessments for large cohorts.