Phenotypic drug discovery (PDD) is increasingly being recognized as a viable compliment to target-based drug discovery (TDD). By measuring functional changes, typically at a systems level, PDD can facilitate the identification of compounds having a desirable pharmacology. This capability is particularly important when studying CNS diseases where drug efficacy may require modulation of multiple targets in order to overcome a robust, adaptive biological system. Here, we report the application of a mouse-based high-dimensional behavioral assay to the discovery and optimization of a structurally and mechanistically novel antipsychotic. Lead optimization focused on optimizing complex behavioral features and no explicit effort was made to identify the target (or targets) involved.