ABSTRACT Young adults living with chronic illness often experience considerable uncertainty across the emotional, cultural and medical spheres of their everyday lives. The process of seeking, receiving and reckoning with a diagnosis has frequently been an in-road for qualitative examinations of these experiences. As a result, the biomedical diagnosis has often taken centre stage in research concerning how uncertainty is managed and/or more stability is found. However, the significance of diagnosis can shift over time, and in many cases, the promise of diagnosis deteriorates as life unfolds. This study draws on a series of in-depth qualitative interviews with 33 young adults (ages 19–29) living with a range of chronic illnesses, which include auto-immune illnesses, fatigue syndromes and neurological conditions. Undertaking an inductive interpretative analysis based on constructivist grounded theory, we examine the role and meaning of diagnosis for our participants and find that they iteratively de-centre diagnosis in various circumstances. We suggest that while the way young adults manage chronic illness may involve seeking a diagnosis, navigating the shortcomings of diagnosis takes a significant emotional toll, and a failure to recognise this work is one important way that the experience of chronic illness when young can be misunderstood. Open access, https://onlinelibrary.wiley.com/doi/10.1111/1467-9566.13861
