Candida species are responsible for the large majority of fungal infections acquired in critically ill patients. Candida infections have become increasingly important. Infections mainly evolve from endogenous colonization facilitated by the use of broad-spectrum antibiotics. The intensity of Candida species colonization constitutes a strong predictor of subsequent infection. Hand carriage of Candida species is, however, highly prevalent in ICUs, and nosocomial transmission has been documented. Careful epidemiologic investigation coupled with intraspecies delineation of Candida strains are frequently necessary for a complete understanding of the infection process. New drugs available will offer better alternatives for earlier intervention strategies.