The Screen-Well® hematopoietic toxicity library is a focused collection of 115 compounds with defined and diverse hematopoietic toxicity, including myelosuppression, neutropenia, leukopenia, anaemia, and many more. A variety of structurally and mechanistically different compound classes are included, as well as nontoxic controls. The compounds are dissolved in DMSO at 10 mM and aliquoted into deep-well plates. The library is an essential tool for predictive toxicology screening and assay development.