New treatment options for managing chemotherapy-induced neutropenia are reviewed. The benefits of using colony-stimulating factors in cancer patients are evolving and include preventing neutropenia and decreasing its severity and duration. However, several areas of controversy regarding chemotherapy-induced neutropenia and the use of colony-stimulating factors remain: dose intensity, which colony-stimulating factor to use and when, and administration. Colony-stimulating factors have not been found to increase overall survival time in patients undergoing chemotherapy, but they are used to prevent febrile neutropenia, reduce hospitalizations, and improve quality of life. The methods of using colony-stimulating factors are also evolving, with altered administration showing potential as a means of reducing treatment cost. If the rate of febrile neutropenia for a given combination chemotherapy regimen is < 40%, routine prophylactic use of colony-stimulating factors is not considered cost-effective and is not recommended by the American Society of Clinical Oncology. Pegfilgrastim is filgrastim to which polyethylene glycol has been added to extend the drug's half-life and permit less frequent administration. The issue of dose intensity will continue to be evaluated as new cytotoxic agents and combinations are introduced. Better models for identifying patients most likely to benefit from colony-stimulating factors are needed.