BY MICHAEL VOSS, BBC News
HAVANA -- Not the new president, Raul, although he has promised to push through "structural and conceptual" changes to this communist island in the Caribbean.
It is Raul's daughter, Mariela Castro.
As head of the government-funded National Centre for Sex Education, she is trying to change people's attitudes towards minority groups in the community.
She is currently attempting to get the Cuban National Assembly to adopt what would be among the most liberal gay and transsexual rights law in Latin America.
The proposed legislation would recognise same-sex unions, along with inheritance rights. It would also give transsexuals the right to free sex-change operations and allow them to switch the gender on their ID cards, with or without surgery.
There are limits: adoption is not included in the bill and neither is the word marriage.
"A lot of homosexual couples asked me to not risk delaying getting the law passed by insisting on the word marriage," Mariela Castro said.
In the early years of the revolution much of the world was homophobic. It was the same here in Cuba and led to acts which I consider unjust
"In Cuba marriage is not as important as the family and at least this way we can guarantee the personal and inheritance rights of homosexuals and transsexuals."
She says that her father is supportive of her work, although he advises her to move slowly.
"I've seen changes in my father since I was a child. I saw him as macho and homophobic. But as I have grown and changed as a person, so I have seen him change."
Mariela's mother, the late Vilma Espin, was an internationally recognised champion of women's rights.
For Mariela, it is the rights of homosexuals and transsexuals that need fighting for.
Once a week, a group of transsexuals gathers for a support session at the old Havana mansion which houses Mariela's Sex Education Centre.
Their ages range from late teens to mid-40s. All are dressed as women; some have had sex-change operations.
A state-funded psychiatrist offers counselling, support and health education.
"Transsexuals have always faced a degree of injustice," said
Libia, right, who trained as a hairdresser after attending sessions at the centre.
"Here we get a lot of respect. This institution has helped raise our self-esteem."
Today Cuba has a vibrant but generally discreet gay scene. There is a popular gay beach in Playas del Este just a short drive from Havana.
In the capital itself there are no openly gay bars, but there is a weekly nightclub complete with floor show.
The venue also hosts a comedy club one night, a cabaret another.
But according to the manager, who asked not to be named or for the club to be identified, it is the gay evening that is always the best attended.
The event is perfectly legal but it is not advertised, relying instead on word of mouth. Given Cuba's past treatment of homosexuals, most people here prefer to remain anonymous.
In the early days of the revolution many homosexuals were sent to forced labour camps for re-education and rehabilitation.
The camps did not last long but still gays were often denied certain jobs as "ideological deviants".
In the 1980s, there were orchestrated mass rallies denouncing homosexuals.
Sex between consenting adults of the same gender was legalised about 15 years ago, but police harassment and raids on gay gatherings continued until very recently.
"In the early years of the revolution much of the world was homophobic. It was the same here in Cuba and led to acts which I consider unjust," said Mariela Castro.
"What I see now is that both Cuban society and the government have realised that these were mistakes. There is also the desire to take initiatives which would prevent such things happening again."
But it remains an uphill struggle. Old prejudices remain deeply ingrained, particularly amongst the older generation.
"It's like an illness or perhaps a character defect," one man explained, asking not to be identified.
Others though are more tolerant. Talking to people in the street, many said that they disapproved of homosexuals but felt that people should be free to live their own lives.
There is still no guarantee that when the National Assembly convenes later this year, under the watchful eye of Raul Castro, it will approve Mariela's gay rights bill.
If it does, though, this would mark a revolutionary change in Cuba's sexual politics.