Device infections in patients supported by a mechanical circulatory support system remain an important problem, particularly as we enter the era of permanent device implantation. This article focuses on fungal infections that occur in patients with ventricular assist devices. The nature of fungal, especially Candida species, colonization and infection in severely ill, hospitalized patients will be described. Information regarding the effect of the artificial surface-blood interface on the immune system's ability to combat fungal organisms will also be presented. Basic aspects of the fungal-host interaction serve as the foundation for a discussion of clinical management protocols for preventing and treating fungal infections in patients supported by a ventricular assist device.