Contra el Borrado de las Mujeres ('Against the Erasure of Women') is a Spanish feminist alliance that opposes replacing the category of biological sex with gender identity in law and official statistics. It argues that gender is the set of norms, stereotypes and roles imposed on people on the basis of sex — not an identity that should take legal priority over women's sex-based rights. The alliance examines how gender self-identification laws affect women and girls across areas such as sport, education, healthcare and child safeguarding. Through policy analysis, educational material and activism it works to defend sex-based protections and to keep women's rights at the centre of the debate in Spain.