Hematopoietic stem cell transplantation (HSCT) is an increasingly common treatment option for malignant and nonmalignant diseases, but it has significant associated morbidity and mortality. Nurses caring for HSCT recipients must be aware of all potential complications, including engraftment syndrome (ES). Previous nursing literature has included little information on this syndrome, which often presents with noninfectious fever, skin rash, and pulmonary infiltrates, and ES may be fatal if left unidentified and treatment is not initiated promptly. Reports of the risk factors, incidence, clinical manifestations, diagnosis, treatment, and outcomes have much variation, likely from a lack of definite diagnostic criteria and inconsistency in the terminology associated with ES. The purpose of this article is to provide an overview of ES and the implications for nursing practice and research.