What is lost, if we don’t have a diagnosis? This article examines the aims of clinical medicine, and the role of understanding in this. Starting from a case prompt with a patient suffering from persistent physical symptoms, I argue that understanding is at the clinical core, and that the target of such understanding is the patient body with symptoms. Synthesising accounts of medical understanding and phenomenology of illness, I suggest that the understanding sought in the clinic extends beyond mechanistic explanation to include a sense of bodily intelligibility, and that diagnoses are useful but not necessary tools to this end.