A gender quota is a quota used by countries and parties to increase the amount of women or substantive equality based on gender in legislatures. Women are largely underrepresented in parliaments and account for a 26.9% average in parliaments globally. As of November 2021, gender quotas have been adopted in 132 countries. Around the world, quotas vary greatly in their enforcement and the stage of electoral process targeted, creating three main types of quotas: legislated candidate quotas, voluntary party quotas, and reserved seats. Regardless of their prevalence, they are a controversial measure, creating debates concerning their impacts, both negative and positive.

Developed by Drude Dahlerup, the definition of quotas contains two dimensions. The first examines what stage political recruitment process the quota targets. They can aim to increase the number of women who have considered running for office, the number of women candidates running, or women holding office. The second factor considers their enforcement, as quotas can either be required by law or voluntary, in which parties can choose to implement them. Based on these variations, there are three main types of gender quotas utilized around the world: aspirant quotas, candidate quotas, and reserved seats.

Considered the least used form of quota, aspirant quotas ensure that some women are nominated for candidacy by a political party, increasing the number of women moving from being eligible to run to being an aspirant. Aspirant quotas are adopted voluntarily on a party-by-party basis in single-member district systems. Examples of these policies include all-women shortlists in the United Kingdom and primaries.

Aspirant quotas are used so little because they are seen as having low effectiveness. One criticism is it targets the beginning of political recruitment, which doesn't guarantee an increase in women legislators. According to Professor Richard Matland, another difficulty of these policies is the local-central struggle for power over candidate selection. Aspirant quotas tend to be implemented by central parties to meet their demands, which can intrude on local party strength.

Found in countries utilizing proportional representation, candidate quotas target the transition from aspirant to candidate by requiring parties to include a certain minimum percentage of women in their candidate lists. Candidate quotas are either statutory or voluntary. Legislated candidate quotas require all parties to abide by the rule and are commonly found in Latin America, such as the Argentine quota law. Thérèse Mailloux who serves as the Chair of the Board of directors for the Groupe Femmes Politique et Démocratie stated that approximately 25 of the top countries a part of the Inter-Parliamentary Union have implemented gender quotas by their constitution or as part of their law.

Voluntary party quotas leave it up to individual parties to implement guidelines regarding how many women are included on party lists. Predominantly found in Europe, these quotas are applied in systems with liberal political culture and left-leaning parties. Voluntary party quotas, like legislated candidate quotas, are most compatible with proportional representation systems. Since the policies are not legally enforced, their effectiveness varies greatly depending on party success and commitment to the policy. One example of a successful voluntary party quota is South Africa, in which the African National Congress committed to a quota and maintains high representation in the South African parliament.

Reserved seats quotas guarantee the number of female legislators holding seats in legislature by setting aside a certain percentage of seats for women. Within reserved seats policies, seats can either be allocated by direction elections or appointments. These policies are implemented in the Middle East, Africa, and Asia.

These case studies will focus on countries who have implemented gender quotas or found alternatives to gender quotas.