This is an open access title available under the terms of a CC BY-NC-ND 4.0 International license. It is free to read at Oxford Academic and offered as a free PDF download from OUP and selected open access locations.Politicians want to stay in power. Because winners attain office under a given set of electoral rules, any change to these rules is puzzling. When electoral reform does take place, it is expected that changes will better serve those already in power. Perhaps more than any other type of electoral rule, gender quotas are explicit about who is set to win and lose from their adoption: although they limit the space for men - the clear majority of incumbents - they are nevertheless present in every region of the world. But how has this happened? In other words, under what conditions are (men) legislators more likely to support the adoption of gender quotas? Resistance to Gender Quotas in Latin America is the first book to closely trace legislators'' behavior towards gender quotas since the policy made its way into plenary debates. It reconstructs three decades of power struggles over quota policymaking in Latin America, and argues that men legislators are more likely to support gender quotas when opposition to the policy could have an impact on their future career prospects. The book draws on a wealth of experimental, quantitative, and qualitative data to show how an institution that explicitly seeks to replace incumbents has successfully spread through Latin America despite resistance from those incumbents. Malu Gatto explores the individual-level characteristics that shape legislators'' resistance towards gender quotas, and provides an overview of the gradual processes through which initially weak quotas that did not impose threats to the status quo became policies that radically transformed the gender composition of legislatures. Finally, the book also explores case studies of quota policymaking in Brazil, Costa Rica, and Chile and shows that incumbents'' self-preservation instincts shape their behaviors towards quotas, delaying the timing of quota adoption, weakening quota designs, and lengthening quota policymaking processes.