Purpose: The purpose of this paper is to assess the relative effects of participation in cooperative education (co-op) and engagement in reflection upon previous work experiences on undergraduate students' vocational self-concept (VSC) at graduation. Design/methodology/approach: A cross-sectional survey of graduating students (n = 1,483) from a Canadian university was used. Regression models and a mediation analysis were used to test the influence of co-op on VSC through the mechanism of reflection. Findings: Results suggest that both co-op and reflection on previous work experiences have direct effects on VSC, and that reflection partially mediates the relationship between degree type and VSC. Research limitations/implications: This supports the role of work-integrated learning and self-reflection as critical determinants of students' work-related learning outcomes, and co-op as a potential container in which reflection may occur. Practical implications: Students should be given opportunity to reflect on their work-related experiences in order to strengthen their VSC. Institutions may integrate practices related to reflection in order for their students to reap the benefits of deeper learning. Originality/value: This study represents an inaugural view of the potential links between self-reflection and the development of students' VSC across both co-op and non-co-op degree types.