The objective of the proposed study is to demonstrate that serial blood volume analysis (BVA) using RI-BVA (BVA-100, Daxor, NY) can be used to guide changes in prescription of dry weight for hemodialysis patients. The knowledge of a patient's ideal BV and degree of hypervolemia using these measurements can be used to change the prescription of DW in an objective way instead of the current standard of practice, which is based on subjective prescription of dry weight. A first study was conducted to determine the rate of plasma volume (PV) re-expansion for each patient as a guide to rate of fluid removal (results published, refer to citations). A second study was conducted in order to assess the value of a BVA measurement in guiding prescription of clinical DW. A follow up BVA would then be done in order to check if patients were closer to ideal BV than prior to changing dry weight.