This publication introduces women’s parliamentary caucuses as flexible, cross-party bodies that advance gender equality and women’s rights within legislatures. It highlights their core roles: building solidarity and mentorship among women leaders, advocating for gender-sensitive laws and policies, and promoting more inclusive parliamentary practices. Drawing on global examples, it shows how caucuses strengthen legal reforms, foster collaboration with civil society, and expand women’s political participation. The guide offers practical considerations to support the effective creation, structure, and functioning of these caucuses in diverse national contexts.