The incidence of renal cell carcinoma (RCC) has gradually increased, and approximately 40% of all patients diagnosed with this disease will die of it. With the increasing availability of ultrasonography and computed tomography (CT) scanning, incidental renal tumors are more frequently diagnosed. Overall, conflicting evidence still exists to support a trend towards early diagnosis and/or a change in the natural history of the disease. The localization of the von Hippel-Lindau (VHL) tumor suppressor gene and other regions on chromosome 3p have contributed significantly to our understanding of the molecular genetics of both familial and sporadic RCC. Moreover, distinction between different cell types of RCC are being made at the molecular and genetic level. A relationship between environmental factors, such as cigarette smoking, and these genetic disturbances has yet to be determined. Although different determinants of nuclear grading are being proposed as prognostic factors, no convincing evidence has been identified to support the use of other molecular markers, such as the p53 tumor suppressor gene and epidermal growth factor. With regard to treatment, beyond the role of surgery in organ-confined RCC, other therapies for RCC are limited. Furthermore, immunotherapy has shown the best promise by providing durable responses in patients with advanced disease.