The advent of high-content screening has expanded the ability of researchers to identify and quantify compound effects on a number of cellular events in a manner that allows for the rapid screening of chemical libraries. We have validated an approach for characterizing inhibitors of Aurora kinase family members using high-content screening by determining compound effects on the levels of the mitotic marker phospho-histone H3 (Ser10). Analysis of the data from these experiments led us to the discovery of a series of related compounds that increased the level of cells staining positive for the mitotic marker, indicating a block of cell cycle progression at M-phase. We then reconfigured the Aurora kinase inhibition assay and validated a high-content approach to identify compounds that block progression through M-phase. We were able to take advantage of the flexibility within the high-content screening platform to measure DNA content, activation of apoptosis, and effects on beta-tubulin staining patterns, all of which directly led to the identification of the cellular target of this new class of compounds.