Candidemia and invasive candidiasis are the most frequent mycoses in critically ill patients in intensive care units. Recently, the number of systemic antifungal agents has increased, leading to improved treatment options. Yet these infections remain to be characterized by poor prognosis and high mortality rates. The most important predisposing factors are yeast colonization of the mucosa or skin and damage to the integrity of the host's natural barriers. Early diagnosis of invasive candidiasis is difficult, since its clinical manifestations are not characteristic and the laboratory techniques are time-consuming and not completely reliable. The currently available treatments comprise three groups of antifungals: triazoles, polyenes and echinocandins. For its effectiveness, low toxicity and reasonable price, fluconazole is the most widespread drug currently used to treat systemic yeast infections. However, despite high treatment costs, echinocandins are becoming the drug of choice. The advantages are a broad spectrum of species, safe administration to patients with kidney and liver damage, minimal drug interactions and fungicidal effects. Candidemia may often be positively influenced by replacing an intravenous catheter. Despite earlier controversy, the latest treatment strategies clearly recommend its removal. Although antifungal prophylaxis lowers the incidence of invasive candidiasis, it is considered to be useful only if targeted to high-risk groups of patients. Empirical treatment of febrile patients not responding to broad-spectrum antibiotic therapy is only effective in wards with a higher incidence of systemic candidiasis, in patients with risk factors and if other causes are reliably excluded.