Emma Watson has revealed she will be a Goodwill Ambassador for the United Nations, promoting gender equality and the empowerment of women.
She confirmed the news on Twitter, writing: "So excited to start work with the AMAZING people at UN Women!"
The international organisation also announced the appointment on the social media site, saying they were "thrilled" the actress was joining them.
News of her role was detailed on the UN Women website, which then crashed.
UN Women is the abbreviated name of The United Nations Entity for Gender Equality and the Empowerment of Women.
It is made up of representatives from around the world, tasked with helping to improve opportunities for women and girls as well as seeking gender equality and tackling discrimination.
In a statement Watson said she was humbled by the role which will give her the chance to "make a real difference".
"Women's rights are something so inextricably linked with who I am, so deeply personal and rooted in my life that I can't imagine an opportunity more exciting," she said.
"I still have so much to learn, but as I progress I hope to bring more of my individual knowledge, experience and awareness to this role."
Phumzile Mlambo-Ngcuka, Under-Secretary-General and Executive Director, UN Women, said: "We are thrilled and honoured to work with Emma, whom we believe embodies the values of UN Women.
"The engagement of young people is critical for the advancement of gender equality in the 21st century, and I am convinced that Emma's intellect and passion will enable UN Women's messages to reach the hearts and minds of young people globally."
The actress has already been involved in promoting girls' education, visiting Bangladesh and Zambia.
She will now work for UN Women's HeForShe campaign which calls for men and boys to stand up against inequalities faced by women and girls around the world.
A number of high profile celebrities have had roles with the UN, including Michael Douglas, Stevie Wonder and Charlize Theron.
Drew Barrymore is an Ambassador Against Hunger for the World Food Programme, which is part of the UN system.
In 2012 Angelina Jolie was appointed Special Envoy of UN High Commissioner for Refugees, having previously been a Goodwill Ambassador, visiting more than 40 countries as part of her role.
Emma Watson rose to fame in the Harry Potter films, in which she starred as Hermione Granger.
The 24-year-old, who recently graduated from Brown University with a degree in English Literature, has also appeared in movies including My Week With Marilyn, The Bling Ring and The Perks of Being a Wallflower.