It is easier to hold a company liable for workplace harassment perpetrated by a supervisor than by a coworker. In Vance v. Ball State University, the Supreme Court attempted to clarify the crucial yet enigmatic definition of “supervisor.” In doing so, the Court created a definition that early commentators criticized as too narrow and too inflexible to capture the varied structures of the modern workplace. In contrast to those commentators, this Note argues that Vance’s definition is flexible enough to encompass all workplaces. Vance’s definition does this by incorporating the tort concept of proximate causation into employment law. As this Note argues, Vance should be read to hold that a supervisor is someone who can proximately cause an employer to take a tangible employment action against another employee.