Participatory projects in museums entail coordinating multiple perspectives, the views and needs of the participants as well as those of museum professionals and researchers. We describe the dialogues and reflexive engagement of museum staff in a ten-month process that involved a group of 11 young people from the multi-ethnic district Grorud in Oslo in the design of the exhibition FOLK – from racial types to DNA sequences. The exhibition opened at the Norwegian Museum of Science and Technology in March 2018. Here, we discuss the different forms and levels of reflection that this participatory process generated through dialogue. We show how judgements and concerns relate to institutional and professional responsibilities, and argue that participatory projects in exhibition design necessitate a constant process of reflection, and setting and adjusting aims in response to challenges.