Abstract The first renal neoplasm was reported nearly 200 years ago. In 1953, about eight renal tumors were described in a well-known textbook on surgical pathology. As a consequence of the contributions of numerous investigators over many decades, the most recent World Health Organization (WHO) classification of renal neoplasms includes about 50 well-defined and distinctive renal tumors, as well as various miscellaneous and metastatic tumors. In addition, a number of emerging or provisional new entities are under active investigation and may be included in future classifications. In this chapter, we examine these diverse and fascinating neoplasms.