Acute lymphoblastic leukaemia (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 paediatric cancers. In this book, the authors present topical research in the study of acute lymphoblastic leukaemia including genome wide association studies in paediatric acute lymphoblastic leukaemia; mice deficient for the Slp65 signalling protein which is a model for ALL; histone deacetylase inhibitors and maintenance therapy in Ph negative adult acute lymphoblastic leukaemia.