The study of the molecular events leading to cellular transformation and cancer has progressed enormously in the last decade. It has become apparent that many genes subject to modification in cancer are, in fact, transcription factors that govern the execution of the genetic program of the cell. Transcription factors can behave either as oncogenes or as tumor suppressor genes. To date only a very limited number of transcription factors have been associated with cancer. Volume 1 deals with several transcription factor families that were first identified in oncogenic retroviruses. Volume 2 brings up-to-date molecular information on several onco- genes, tumor suppressor genes or chromosomal translocations. Each chapter contains a comprehensive description of the structure of such transcription factors, the nature of target genes, the regulation of their activities and a plausible explanation of how they can deregulate cell growth and differentiation. These volumes are addressed both to the specialized scientist and to an advanced student.