Signaling through the vitamin D receptor has been shown to be biologically active and important in a number of preclinical studies in prostate and other cancers.Epidemiologic data also indicate that vitamin D signaling may be important in the cause and prognosis of prostate and other cancers.These data indicate that perturbation of vitamin D signaling may be a target for the prevention and treatment of prostate cancer.Large studies of vitamin D supplementation will be required to determine whether these observations can be translated into prevention strategies.This paper reviews the available data in the use of vitamin D compounds in the treatment of prostate cancer.Clinical data are limited which support the use of vitamin D compounds in the management of men with prostate cancer.However,clinical trials guided by existing preclinical data are limited.