Mariela Castro is a Member of the Cuban Parliament (Asamblea Nacional del Poder Popular de Cuba) and Director of the Cuban National Center for Sex Education (CENESEX).
CENESEX campaigns for effective AIDS prevention as well as recognition and acceptance of homosexuality, bisexuality, transvestitism, transsexuality and human rights.
In 2005 she proposed a project to allow transgendered Cubans to receive sex reassignment surgery and change their legal gender. The measure became law in June 2008 and sex reassignment surgery is now available to Cubans without charge.
Mariela Castro is also president of the Cuban Multidisciplinary Centre for the Study of Sexuality, president of the National Commission for Treatment of Disturbances of Gender Identity, member of the Direct Action Group for Preventing, Confronting, and Combating AIDS, and an executive member of the World Association for Sexual Health (WAS).
She is also the director of the journal Sexología y Sociedad, a magazine of sexology edited by CENESEX. She has published 13 scholarly articles and nine books.