The unique phenotype of each differentiated cell in an animal (or plant) arises from selective expression of genes in a cell- or tissue-specific fashion, which is controlled primarily at the level of transcription. This review will focus on transcription factors that regulate cell-specific transcription in one intensely studied cell type, the hepatocyte or parenchymal liver cell. All of the recently isolated transcription factors that are important in hepatocyte-specific gene expression were identified in adult liver and there are strong hints that some of these may play an important role in embryogenesis.