Antiangiogenics are the mainstay of treatment in patients with metastatic renal cell carcinoma. Conventional clinical end-points, used to measure efficacy with chemotherapeutic agents, have not been helpful in monitoring the efficacy of antiangiogenic therapy. Increasing numbers of predictive and pharmacodynamic biomarkers are being investigated that are useful surrogates for clinical response and also to identify patients early on who will benefit from this class of agents. This is valuable in avoiding unnecessary toxicity in patients and also in reducing cost implications of this expensive group of drugs.