Skeletal complications are a major cause of prostate cancer morbidity. Gonadal steroid deprivation, the mainstay of treatment for advanced prostate cancer, may contribute to the skeletal morbidity of prostate cancer by accelerating bone loss and increasing the rate of osteoporotic fractures. In addition, changes in the bone microenvironment that accompany gonadal steroid deprivation may promote the growth of skeletal metastases. The goal of my research is to understand and prevent the skeletal complications of prostate cancer. Current research efforts will determine the magnitude of bone loss in men with prostate cancer, evaluate the effectiveness of several treatment strategies, and investigate the mechanisms of treatment-related bone loss. Related research efforts include evaluation of the effects of gonadal steroid deprivation on body composition, including muscle size and strength.