Cytokine therapy with interferon-alpha and interleukin-2 has arguably been the standard treatment for patients with metastatic renal cell carcinoma for more than 20 years. In this paper, the current evidence for the use of cytokine therapy in this patient population is discussed, including the significant toxicity associated with these agents. A low overall response rate and a marginal survival advantage are observed with interferon-alpha and interleukin-2; however, these therapies have significant toxicity and impair quality of life. Unlike the current tyrosine-kinase inhibitors, complete tumour responses may be seen with interleukin-2, but again this therapy has significant morbidity and mortality. Newer anti-angiogenesis agents may be combined with current standard cytokine therapy for patients with metastatic renal cell carcinoma.