Sodium and water are the main determinants of body volume status and BP. Because sodium and water are excreted by the kidneys, maintenance of volume homeostasis is particularly challenging in hemodialysis (HD) patients. Various interventions have been proposed to avoid fluid accumulation in HD patients, including restriction of dietary sodium intake, ultrafiltration to reach dry weight, and increased plasma to dialysate sodium concentration ([Na+]D) gradient. However, strong evidence for selection of [Na+]D is lacking and there was no consensus in the recent KDOQI guideline.