The foundation of Toxicogenomics is a reference data collection and the tools and expertise to apply this contextual information. DrugMatrix® is the largest existing molecular toxicology reference database and informatics system. DrugMatrix is a unique reference set of gene expression profiles based on benchmark molecules that are anchored to classic pharmacology, toxicology and clinical pathology measurements. Iconix has populated DrugMatrix with the comprehensive results of thousands of highly controlled and standardized toxicological experiments in which rats or cultured rat cells are systematically treated with therapeutic, industrial and environmental chemicals at both non-toxic and toxic doses. Following the administration of these compounds in vivo, complete studies of the effects of these compounds are carried out at multiple time points and in multiple target organs. These studies include extensive pharmacology, clinical chemistry, hematology, histology, body and organ weights and clinical observations. Additionally, a curation team extracts all relevant information on the compounds from the literature, PDR, package inserts and other relevant sources. The heart of the DrugMatrix database is the large-scale gene expression data generated by extracting RNA from the toxicologically relevant organs and tissues and applying these RNAs to both the GE Codelink™ 10,000 gene rat array, and more recently the Affymetrix® whole genome 230 2.0 rat array. The latest release of DrugMatrix contains the profiles derived from administering 638 different compounds to rats. Compounds include FDA approved drugs, drugs approved in Europe and Japan, withdrawn drugs, drugs in preclinical and clinical studies, biochemical standards, and industrial and environmental toxicants.