Covalent modifications to histone proteins play a critical role in regulating gene transcription. Previous studies have used chromatin immunoprecipitation (ChIP) based microarray assays to profile genomic regions that are enriched or depleted for a particular histone modification. Such studies have been conducted extensively in the yeast Saccharomyces cerevisiae, but currently no comprehensive data repositories or analysis tools are available for these data sets. For this reason, we have developed the ChromatinDB database, which contains genome-wide ChIP data for 22 different histones or histone modifications in S. cerevisiae. ChromatinDB provides novel tools to facilitate the visualization and statistical analysis of chromatin features for user-selected gene sets.