The current cure rate of childhood acute lymphoblastic leukemia has reached 80% in many industrialized countries, but in developing countries the rate is often less than 10%. To advance the cure rate, investigators have formed several parallel initiatives in both industrialized and developing countries through international collaboration and partnership. Among industrialized countries, investigators have combined data to conduct in-depth studies of the biology and heterogeneity of high-risk or drug-resistant subgroups of leukemia to identify optimal or novel treatments. Alliances have been established among government, local nongovernmental organizations, health care providers, and international groups to improve the survival rate of childhood leukemia in developing countries. "Twinning" partnerships between a well-established individual institution or study group and a pediatric cancer unit in a developing country has proved to be the most successful strategy to date.