Beyond competitive elections, democratisation should include a transformation of the institutions of state and civil society into spaces that recognise the rights of citizens and allow for their participation. This study explores the question of how Mexican labour unions are transformed into institutions with a commitment to the rights and participation of women workers. Drawing on evidence from five unions, the paper shows that compared to their corporatist counterparts, unions with a ‘democratic ethos’ provide a context within which gender equity rights are more readily recognised. However, recognition of gender equity is primarily dependent on feminist activism and union leadership. The paper argues that women's efforts to transform their unions into spaces that reflect and advocate for gender equity rights are critical to strengthening democratic citizenship in Mexico.