Feedback on assessed work is invaluable to student learning, but there is a limit to the amount of feedback an instructor may provide. Peer feedback increases the volume of feedback possible, but potentially reduces the quality of the feedback. This research proposes a model of collaborative peer feedback designed to increase quality of peer feedback, and describes its implementation in an undergraduate mathematics module. The implementation includes the development of bespoke software to automate administrative tasks. [For the complete proceedings, see ED579282.]