The increased detection of incidental renal masses has introduced new challenges into the management of patients with newly discovered renal masses. Much interest has been focused on the diagnostic accuracy and the prognostic ability of imaging studies. These studies have elucidated trends that can guide management but remain woefully inaccurate for predicting the exceptions to the rule, many of which can produce untoward outcomes. Renal biopsy may aid in the management of patients with indeterminate imaging; however, the role of biomarkers remains unclear. Active surveillance has emerged as an attractive option in certain patient populations, although the lack of reliable predictors of tumor behavior based upon currently available surveillance techniques understandably raises concerns about its propriety. For patients who would benefit from operative management, nephron-sparing procedures such as ablation and partial nephrectomy have gained increasing acceptance as an alternative to radical nephrectomy.