Ependymomas are one of the most common pediatric malignant brain tumors. Prognosis, especially in young children, remains poor due to their inherent chemo- and radio-resistance and effective treatment remains one of the more difficult tasks in pediatric oncology: up to half of the patients may die from the disease. The only reproducible prognostic factor is the extent of surgery; neither histological grading nor other biomarkers can be used to reliably make treatment decisions in clinical practice. None of the studies identifying new biomarkers have been conducted prospectively, only few have been undertaken within the context of a clinical trial and most have been conducted with limited samples (often including adults and childhood samples). International collaboration is needed to improve ependymoma prognostication.