The story of how we got from he and she to zie and hir and singular they. Like trigger warnings and gender-neutral bathrooms, pronouns are suddenly sparking debate, prompting new policies in schools, workplaces, even prisons, about what pronouns to use. Colleges ask students to declare their pronouns; corporate conferences print nametags with space for people to add their pronouns; email signatures sport pronouns along with names and titles. Far more than a byproduct of campus politics or culture wars, gender-neutral pronouns are in fact nothing new. Renowned linguist Dennis Baron puts them in historical context, demonstrating that Shakespeare used singular they; that women evoked the generic use of he to assert the right to vote (while those opposed to women's rights invoked the same word to assert that he did not include she), and that self-appointed language experts have been coining new gender pronouns, not just hir and zie but hundreds more, like thon, ip, and em, for centuries. Based on Baron's own empirical research, What's Your Pronoun? tells the untold story of gender-neutral and nonbinary pronouns.