Chromosome copy number alterations, otherwise known as aneuploidies, are a ubiquitous feature of human tumors. My lab has developed an innovative set of chromosome engineering tools that allow us for the first time ever to create and eliminate specific aneuploidies in mammalian cells. We plan to use these tools as platforms for drug and CRISPR screens to identify therapeutic vulnerabilities caused by specific aneuploidies. Drugs designed to selectively target aneuploid cells could exhibit broad efficacy across multiple cancer types while also having few side effects in normal, untransformed tissue.