Chemical series emerging from a successful HTS campaign can be analyzed and optimized at the High-Throughput Molecular Screening Center through the use of computer-aided strategies. These include: (a) analysis of screening data to eliminate false positives and off-target activity, (b) prediction of physical and biological properties of small molecules to flag non-druglike functionalities and chemical reactivity, (c) molecular similarity and diversity searching, (d) Structure Activity Relationship (SAR) analysis and SAR by purchase from commercial libraries (> 5 million compounds), (e) virtual library enumeration of active lead compounds, and (f) design and custom synthesis of lead-candidates and novel analogs.