Secondary hyperparathyroidism from inadequate calcium absorption in the gut, is the underlying pathophysiology for rachitic changes in hereditary vitamin D–resistant rickets (HVDRR). We describe a novel use of Cinacalcet to treat a child with HVDRR in whom conventional modes of therapy had to be discontinued. Cinacalcet therapy with high-dose oral calcium effectively normalized the metabolic abnormalities and bone condition. The relative ease of administration of the calcimimetic as a once- or twice-daily oral preparation, compared with traditional intravenous calcium administration, should encourage its move to the frontline of treatment of the disorder. © 2013 American Society for Bone and Mineral Research.