Evidence supporting the role of hematopoietic stem cell transplantation (SCT) in the therapy of acute lymphoblastic leukemia (ALL) in children is presented and critically evaluated in this systematic evidence-based review. Specific criteria were used for searching the published literature and for grading the quality and strength of the evidence and the strength of the treatment recommendations. Treatment recommendations based on the evidence are presented in a table in this review (Summary of Treatment Recommendations Made by the Expert Panel for Pediatric Acute Lymphoblastic Leukemia) and were reached unanimously by a panel of ALL experts. The priority areas of needed future research in pediatric ALL are unrelated marrow or blood donor versus unrelated cord blood donor allogeneic SCT; alternative, nonfamily allogeneic donor versus autologous SCT; better methods for identifying high-relapse-risk patients; assessments of the effect of current chemotherapy regimens on early relapse; and use of pre-SCT detection of minimal residual disease to predict post-SCT outcomes.