Clinical concepts--labels placed on categories of sickness--are essential to both the physician's and the patient's understanding of a disease. The changing use of labels in renal medicine reflected how physicians and others thought about kidney disease, each new label suggesting increasing complexity in the encounter of renal patient and physician. While dropsy referred to symptoms easily perceived by the patient as well as the physician, Bright's disease focused mainly on microscopic pathology invisible to the patient. Most removed from palpable symptoms is end-stage renal disease, a diagnosis often uncovered by autoanalyzer, defined by the need for dialysis, and formally bestowed by government. This process of definition and redefinition demands the attention of scholars because it reveals much about the evolution of medical thought and practice.