Prototyping groups can be an important tool for developing ideas with the help of participant feedback, but they raise questions about collaboration and shared authorship. In setting up an interdisciplinary prototyping group at Manchester Metropolitan University, we’ve incorporated clear propositions for co-design and a rotating focus on the projects of different group members. In this workshop, we will share what we’ve learned and work together to create a code of conduct for prototyping spaces that is clear, adaptable, and ethical.