Studies on prophylaxis of infection in neutropenic patients continue to dominate the literature. It is clear that vancomycin, quinolones and azole antifungals are effective but must be used with caution; however, superinfection with alpha-haemolytic streptococci, quinolone-resistant coliforms and the emergence of resistant enterococci are dependent on many factors, not just over-use of particular antibiotics. Azole-polyene antifungal combinations appear to be effective in animal studies. Adjunctive treatment with colony-stimulating factors, particularly of established fungal infections and other immunotherapy, remains promising but clinical trials are urgently required.