An analysis of the normal tissue effects of irradiation of the kidney is presented. Various clinical syndromes resulting from treatment are described as well as the potential cellular basis for these findings. Effects of concurrent and/or sequential treatment with irradiation and various chemotherapeutic agents are discussed and the impact of these agents on toxicity presented. Adverse consequences of renal treatment in the child is described and possible radiation effects on so-called compensatory hypertrophy following nephrectomy presented. Renal consequences described to date of bone marrow transplantation programs utilizing irradiation are also presented. The necessity of a dose-volume histogram analysis approach to analyzing renal toxic effects in patients followed for long (> 10 year) periods is essential in developing accurate guidelines of renal tolerance.