Eligible hemodialysis patients who are currently receiving an erythropoiesis stimulating agent (ESA) who enrol and sign consent will be randomized on a 1:1 basis to either remain on epoetin alfa or switch to darbepoetin alfa as their anemia therapy. Patients will be dosed with the assigned drug using a study algorithm to maintain their hemoglobin (Hb) level within the currently recommended range (100-120 g/L). There will be an initial "run in" period of a minimum of six weeks to ensure the patient's hemoglobin is stable within the target range. The trial itself will run for a subsequent twelve months (active phase). Every effort will be made to ensure that Hb stays within the target range during the study period. The primary outcome will be the total cost of each ESA therapy over the twelve month active phase. Data including Hgb, iron indices and dosing, and clinical events will be obtained from electronic sources and from the attending physicians and/or the clinical pharmacist.