The University of Michigan Center for Chemical Genomics (CCG) provides high-throughput screening of extensive small molecules, natural product extracts, and siRNA libraries, as well as assay development and optimization, for basic biology and drug discovery projects. The CCG has more than 250,000 diverse small molecule compounds, a unique library of more than 50,000 natural product extracts, an extensive siRNA library, and a growing library of FDA-approved compounds for drug repurposing projects. We also offer MScreen, a cost-effective web-based data storage and analysis tool developed to help users streamline the hit-to-lead decision process. The CCG services are available to U-M researchers and external academic and industry partners.