Invasive candidiasis is rare in the general population (about 8 episodes/100,000/year), but has a higher incidence in hospitalised patients (0.5/1000 admissions). It complicates about 10 per 1000 admissions in critical care, where it represents 10-15% of all nosocomial infections. Candidiasis remains difficult to diagnose and its mortality is as high as those of septic shock (40-60%). A better knowledge of the pathophysiology of the disease and the availability of triazole compounds that are less toxic than amphotericin have given rise to the concept of early empirical or preemptive treatment. Prophylaxis of invasive candidiasis, which is very effective, is based on risk factor identification. However, prophylaxis must be restricted to carefully selected groups of patients, to avoid the emergence of resistant strains and a shift in the distribution of pathogens from albicans to non-albicans strains under the pressure of antifungal agents.