Hack et al. described a novel approach for enhancing the diversity of chemical libraries. Compounds for potential acquisition (filtered to remove non-drug-like compounds) were added to those in a corporate library, and the overall group was organized into clusters using an algorithm that emphasized common substructures. Clusters that were populated exclusively by external compounds were then presented to medicinal chemists, who used community voting to prioritize which clusters should be acquired. The authors noted that the goal of enhancing the diversity of the chemical library was met, and the voting preferences reflected current views on lead-likeness.