Clinicians do not have the same awareness of pain as patients. In some circumstances, the patients' pain is too distant from the clinicians' experience, making difficult for them to understand what the patient is talking about. To overcome this lack of understanding, a growing movement is emerging in psychiatry which value experiential expertise through the development of partnership with expert patients. The patient-researcher or peer-researcher is a figure that exemplifies the involvement in scientific research projects of a person with a history of mental disorders. This article discusses in detail the challenges related to the coproduction of knowledge in psychiatric research.