Molecular markers for renal cell carcinoma could guide early detection of localized disease in defined populations at high risk for the disease or early disease recurrence after nephrectomy for renal cell carcinoma. In addition, sensitive and specific markers may provide surrogate end points for clinical trials of treatment and/or disease prevention. Powerful techniques of genomic and proteomic analysis of human renal carcinoma cell lines, tumor samples, and biological fluids, such as plasma and urine, obtained from patients with renal cell carcinoma, are likely to identify candidate markers. Careful selection among early candidate markers and further testing in independent patient populations are required for marker validation.