Most (>80%) cancers involving the kidney are renal cell carcinoma (RCC). One third of patients diagnosed with kidney cancer have evidence of metastatic disease at the time of diagnosis, and as many as half of patients treated for localized disease eventually relapse. As is true for any other malignancy, one must determine which tumor features, patient factors, and laboratory techniques will provide diagnostic and prognostic information for patients with RCC. This article focuses on the history and rationale of the current staging systems for RCC as well as the potential for improvements by the addition of other clinical, pathologic, and molecular prognostic markers.