Since its isolation exactly a decade ago, B-Myb has intrigued a growing number of scientists interested in understanding the mechanisms of cell proliferation. In many aspects the B-Myb story resembles that of a fashionable transcription factor involved in cell cycle control: E2F-1. Similar to E2F-1, B-Myb is a transcription factor whose expression is regulated at the G1/S border of the cell cycle. Given the ubiquitous expression of B-Myb within different cell types, its link with the cell cycle, and augmented expression in transformed cells, studies are in progress to define the potential role of B-Myb in human cancer. The purpose of this review is not to provide an extensive background to the B-Myb field but rather to describe the latest developments. A comprehensive outline of B-Myb structure and function can be found in the review by Saville and Watson (1998a, Adv. Cancer Res., 72:109-140).