Hepcidin, a small 25 amino acid peptide, has been well established as the iron regulatory hormone. Its expression is upregulated in response to iron and inflammatory cytokines, and downregulated in anemic or hypoxic states. Hepcidin decreases iron export into the plasma by binding to and inducing the degradation of ferroportin, an iron channel located on macrophages and the basolateral surface of enterocytes. This leads to decreased absorption of parental iron by the enterocytes, reduced recycling of erythrocyte iron by macrophages, and increased iron stores in the hepatocytes. Although hepcidin assays are not currently approved for clinical use in the United States, there is much interest in the potential use of this biomarker for management of iron related medical conditions. This review briefly summarizes the current hepcidin test platforms under investigation and the challenges associated with development of a clinical assay for this biomarker. In addition, selected potential future applications hepcidin testing in the clinical setting are addressed. Am. J. Heamtol. 88:976-978, 2013. © 2013 Wiley Periodicals, Inc.