Improvement in supportive care including the introduction of new antibiotics, antiviral and antifungal agents and haematopoietic growth factors have all contributed to a decreased chemotherapy-related mortality and morbidity in cancer patients. However, infections/septic shock during neutropenia still constitutes a major threat to these patients. Most patients develop fever during neutropenia and in 20-40% a manifest bacteremia is documented. In patients with prolonged neutropenia, the risk for fungal infections is increased. The spectrum of bacterial, fungal and viral infections in the neutropenic patient is reviewed.