The Infectious Diseases Working Party of the German Society of Haematology and Oncology presents their guidelines for the treatment of fungal infections in patients with hematological and oncological malignancies. These guidelines are evidence-based, considering study results, case reports and expert opinions, using the evidence criteria of the Infectious Diseases Society of America (IDSA). The recommendations for major fungal complications in this setting are summarized here. The primary choice of therapy for chronic candidiasis should be fluconazole, reserving caspofungin or amphotericin B (AmB) for use in case of progression of the Candida infection. Patients with candidemia (except C. krusei or C. glabrata) who are in a clinically stable condition without previous azole prophylaxis should receive fluconazole, otherwise AmB or caspofungin. Voriconazole is recommended for the first-line treatment of invasive aspergillosis. The benefit of a combination of AmB and 5-flucytosine has not been demonstrated except in patients with cryptococcal meningitis. Mucormycosis is relatively rare. The drug therapy of choice consists of AmB, desoxycholate or liposomal formulation, in the highest tolerable dosage. Additional surgical intervention has been shown to achieve a lower fatality rate than with antifungal therapy alone. The role of interventional strategies, cytokines/G-CSF, and granulocyte transfusions in invasive fungal infections are further reviewed. These guidelines offer actual standards and discussions on the treatment of oropharyngeal and esophageal candidiasis, invasive candidiasis, cryptococcosis and mould infections.