Acute lymphoblastic leukemia (ALL) is a malignant disorder of the bone marrow in which a lymphoid precursor cell becomes genetically altered resulting in dysregulated proliferation and clonal expansion of neoplastic cells. It is the most common malignancy in children, representing nearly one third of all pediatric cancers. In this book, the authors present topical research in the study of acute lymphoblastic leukemia including genome wide association studies in pediatric acute lymphoblastic leukemia; mice deficient for the Slp65 signaling protein which is a model for ALL; histone deacetylase inhibitors and maintenance therapy in Ph negative adult acute lymphoblastic leukemia.