In the past year, great strides have been made in our understanding of the regulatory networks that control gene expression in the model eukaryote Saccharomyces cerevisiae. The development and use of a number of genomic tools, including genome-wide location and expression analysis, has fueled this progress. In addition, a variety of computational algorithms have been devised to mine genomic sequence for conserved regulatory motifs in co-regulated genes. The recent description of the genetic network controlling the cell cycle illustrates the tremendous potential of these approaches for deciphering gene expression regulatory networks in eukaryotic cells.