The present study examined the role of interpersonal variables (psychological safety, value diversity, interdependence, and trust) and conceptions of peer assessment in vocational education. An intervention was conducted (N=45) with a control group (N=17), which indicated change in psychological safety, value diversity, and trust in the peer as an assessor. Furthermore, when comparing the intervention and control group, peer assessment contributed to psychological safety and lower value diversity. Perceived learning was predicted by value diversity and conceptions. Conceptions were predicted by psychological safety, value diversity, and trust in the self and in the peer as an assessor. (Contains 3 tables and 2 figures.)