Burkitt's lymphoma, a pathological entity initially described in Africa, is the most common childhood lymphoma in western countries and represents approximately 5% of all adults lymphomas. This high grade small non-cleaved diffuse lymphoma is a model with which to study the relations between cancer and viruses, the chromosomes and the genes. Burkitt's lymphoma is also a model for clinical research which allows evaluation of the dose effect concept with chemotherapy and the role of megatherapy with autologous bone marrow rescue.