Insights into the regulation of immune cell lineage differentiation and specification as well as into the control of lineage integrity, stability and plasticity are of fundamental importance to understanding innate and adaptive immune responses. In this volume, leading experts provide an up-to-date and comprehensive overview of recent advances in the transcriptional control mechanisms and transcription factor networks that regulate these processes in a variety of different immune cell lineages. The chapters cover the regulation of T versus B cell lineage choice, discuss early B cell development and pre-B cell leukemia prevention, address transcriptional control mechanisms during the differentiation, in regulatory T cells and iNKT cells, detail