Endomebase is a web-based crossspecies resource describing gene and protein expression in the endometrium. It also provides information regarding the biological function of genes, their mutations, and resulting disease conditions (i.e. endometriosis). Links to web sites containing sequence, structure, and more in depth functional information are provided Researchers can search Endomebase to find patterns of coordinate gene or protein expression. These patterns may not otherwise be identifiable using existing technologies. Endomebase may help researchers sift through the ever-increasing amounts of expression data and serve as a model for other tissue-specfic databases.