Hematopoietic stem cell transplantation (HCT) is a treatment for some life-threatening cancers and nonmalignant disorders. As HCT is a curative treatment, it is used to treat children where necessary. It has historically been a dangerous procedure, but advances in medicine have increased the number of long-term survivors. This increase has also revealed late effects in childhood survivors, most notably growth impairment and short stature, which are common after HCT.