The purpose of this study is to assess the Aranesp® dose administered intravenously (IV) once weekly to maintain hemoglobin (Hgb) levels in hemodialysis subjects who are either recombinant human erythropoietin (rHuEPO) naïve or subjects converted from rHuEPO therapy administered IV thrice weekly (TIW).

Inclusion Criteria: - Subjects with end stage renal disease (ESRD) on hemodialysis Exclusion Criteria: - Known hypersensitivity to Aranesp® (darbepoetin alfa) or any of its excipients - Participating in an investigational drug or device trial - Patient will not be available for follow-up assessment - Patient has any disorder that compromises the ability of the patient to give written informed consent and/or to comply with study procedures