Pediatric hematology oncology encompasses perturbations of the several-formed elements of the blood and their precursors in the bone marrow, as well as the coagulation-fibrinolytic systems in the plasma, the reticuloendothelial system, and malignancies of the blood and solid tissues and organs.

Primary clinical duties are diagnosing and treating children with cancer and a variety of different blood disorders. Often these diagnoses (e.g. inherited disorders of coagulation or malignant bone sarcoma) allow the specialist to form close relationships with patients and families to guide them through complex decisions or life-threatening conditions. Outpatient hematology practice includes the evaluation and management of patients with benign disorders. Due to the acuity and complexity of the patients, clinical care also depends on communication and collaboration with an interdisciplinary team of medical sub-specialists.