We aimed to provide recommendations on the infusion duration of anthracycline chemotherapy agents in children with cancer. This study also serves as a practice example of the essential steps that need to be taken when using a previously published systematic review to develop a high-quality clinical practice guideline. Although evidence was scarce and included adult studies, the panel was able (using the Grading of Recommendations Assessment, Development and Evaluation evidence-to-decision framework) to recommend in favor of an anthracycline infusion duration of at least 1 hr (strong recommendation, very low to moderate quality of evidence). Recommending a precise optimal prolonged infusion duration was currently not possible