Pathogenic microbes have evolved a large array of adaptations that allow them to survive and proliferate in the human host environment. Candida albicans is a commensal organism of human epithelia that also constitutes the most common systemic fungal pathogen, increasingly prevalent among immunosuppressed patients. We focus on two distinct adaptations of this organism to the host environment: the ability to use host hemoglobin as heme and iron sources, and the ability to switch between yeast and mold morphologies, enabling C. albicans to spread, attach and penetrate host tissues.