Bone marrow transplantation is an effective treatment for a growing list of disease processes both malignant and non-malignant. Complications associated with marrow transplantation may be related to ablative therapy, immunosuppression, graft-versus-host disease, and recurrence of the underlying disease. Survival depends upon prompt recognition of problems and timely institution of specific interventions, both medical and nursing. Nurses caring for bone marrow transplant recipients face a never-ending and ever-changing challenge to stay on top of the day-to-day problems and patient care crises that can occur.