Within mental health research, there has been a growing recognition of the importance of the knowledge obtained through lived experiences of illness, treatment, recovery, and health. In recent years, the field of eating disorders has seen an emergence of co-produced knowledge, in particular in the co-design of patient-facing materials for use in clinical settings, and a growing body of rich qualitative research by those who may straddle the identities of clinician, researcher and person with lived/living experience. However, there are significant variations in how expertise by experience is defined and utilised within research and clinical practice, and persisting inequities in the extent to which people with lived experience are afforded the agency to define their illnesses and treatment. This paper’s authorship is a collaboration between those with personal and professional relationships with the subject of eating disorders, bringing to life the concept of sharing power and decision-